WO2007111004A1 - Catalyseur de purification de gaz d'echappement, son procede de regeneration, appareil de purification de gaz d'echappement l'utilisant et procede de purification de gaz d'echappement - Google Patents

Catalyseur de purification de gaz d'echappement, son procede de regeneration, appareil de purification de gaz d'echappement l'utilisant et procede de purification de gaz d'echappement Download PDF

Info

Publication number
WO2007111004A1
WO2007111004A1 PCT/JP2006/324068 JP2006324068W WO2007111004A1 WO 2007111004 A1 WO2007111004 A1 WO 2007111004A1 JP 2006324068 W JP2006324068 W JP 2006324068W WO 2007111004 A1 WO2007111004 A1 WO 2007111004A1
Authority
WO
WIPO (PCT)
Prior art keywords
exhaust gas
catalyst
noble metal
carrier
amount
Prior art date
Application number
PCT/JP2006/324068
Other languages
English (en)
Japanese (ja)
Inventor
Miho Hatanaka
Toshitaka Tanabe
Yasutaka Nagai
Toshio Yamamoto
Kazuhiko Dohmae
Nobuyuki Takagi
Masahide Miura
Yasuo Ikeda
Original Assignee
Kabushiki Kaisha Toyota Chuo Kenkyusho
Toyota Jidosha Kabushiki Kaisha
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP2006089120A external-priority patent/JP4775953B2/ja
Priority claimed from JP2006089177A external-priority patent/JP4775954B2/ja
Application filed by Kabushiki Kaisha Toyota Chuo Kenkyusho, Toyota Jidosha Kabushiki Kaisha filed Critical Kabushiki Kaisha Toyota Chuo Kenkyusho
Priority to CNA2006800541044A priority Critical patent/CN101415490A/zh
Priority to CA2648314A priority patent/CA2648314C/fr
Priority to BRPI0621483-5A priority patent/BRPI0621483A2/pt
Priority to EP06823547A priority patent/EP2000202A4/fr
Priority to US12/225,692 priority patent/US8105561B2/en
Publication of WO2007111004A1 publication Critical patent/WO2007111004A1/fr
Priority to ZA2008/09153A priority patent/ZA200809153B/en

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/92—Chemical or biological purification of waste gases of engine exhaust gases
    • B01D53/94—Chemical or biological purification of waste gases of engine exhaust gases by catalytic processes
    • B01D53/9445—Simultaneously removing carbon monoxide, hydrocarbons or nitrogen oxides making use of three-way catalysts [TWC] or four-way-catalysts [FWC]
    • B01D53/945—Simultaneously removing carbon monoxide, hydrocarbons or nitrogen oxides making use of three-way catalysts [TWC] or four-way-catalysts [FWC] characterised by a specific catalyst
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
    • B01J23/54—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/56—Platinum group metals
    • B01J23/58—Platinum group metals with alkali- or alkaline earth metals
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/92—Chemical or biological purification of waste gases of engine exhaust gases
    • B01D53/94—Chemical or biological purification of waste gases of engine exhaust gases by catalytic processes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/96—Regeneration, reactivation or recycling of reactants
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/002—Mixed oxides other than spinels, e.g. perovskite
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
    • B01J23/54—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/56—Platinum group metals
    • B01J23/63—Platinum group metals with rare earths or actinides
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/89—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with noble metals
    • B01J23/8933—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with noble metals also combined with metals, or metal oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/894—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with noble metals also combined with metals, or metal oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with rare earths or actinides
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/89—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with noble metals
    • B01J23/8933—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with noble metals also combined with metals, or metal oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/8946—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with noble metals also combined with metals, or metal oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with alkali or alkaline earth metals
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/90—Regeneration or reactivation
    • B01J23/96—Regeneration or reactivation of catalysts comprising metals, oxides or hydroxides of the noble metals
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/02—Impregnation, coating or precipitation
    • B01J37/0201—Impregnation
    • B01J37/0205—Impregnation in several steps
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/02—Impregnation, coating or precipitation
    • B01J37/0201—Impregnation
    • B01J37/0207—Pretreatment of the support
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J38/00—Regeneration or reactivation of catalysts, in general
    • B01J38/04—Gas or vapour treating; Treating by using liquids vaporisable upon contacting spent catalyst
    • B01J38/10—Gas or vapour treating; Treating by using liquids vaporisable upon contacting spent catalyst using elemental hydrogen
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J38/00—Regeneration or reactivation of catalysts, in general
    • B01J38/04—Gas or vapour treating; Treating by using liquids vaporisable upon contacting spent catalyst
    • B01J38/12—Treating with free oxygen-containing gas
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N11/00—Monitoring or diagnostic devices for exhaust-gas treatment apparatus, e.g. for catalytic activity
    • F01N11/002—Monitoring or diagnostic devices for exhaust-gas treatment apparatus, e.g. for catalytic activity the diagnostic devices measuring or estimating temperature or pressure in, or downstream of the exhaust apparatus
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2255/00—Catalysts
    • B01D2255/10—Noble metals or compounds thereof
    • B01D2255/102—Platinum group metals
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2523/00—Constitutive chemical elements of heterogeneous catalysts
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/30—Catalysts, in general, characterised by their form or physical properties characterised by their physical properties
    • B01J35/391—Physical properties of the active metal ingredient
    • B01J35/393—Metal or metal oxide crystallite size
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/30—Catalysts, in general, characterised by their form or physical properties characterised by their physical properties
    • B01J35/391—Physical properties of the active metal ingredient
    • B01J35/394—Metal dispersion value, e.g. percentage or fraction
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
    • B01J35/61—Surface area
    • B01J35/613—10-100 m2/g
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/02—Impregnation, coating or precipitation
    • B01J37/0201—Impregnation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/02—Impregnation, coating or precipitation
    • B01J37/03—Precipitation; Co-precipitation
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2550/00—Monitoring or diagnosing the deterioration of exhaust systems
    • F01N2550/02—Catalytic activity of catalytic converters
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
    • F01N3/18—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control
    • F01N3/20—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control specially adapted for catalytic conversion ; Methods of operation or control of catalytic converters
    • F01N3/2006—Periodically heating or cooling catalytic reactors, e.g. at cold starting or overheating
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/12—Improving ICE efficiencies
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/40—Engine management systems

Definitions

  • the present invention relates to an exhaust gas purification catalyst, a regeneration method thereof, an exhaust gas purification apparatus using the same, and an exhaust gas purification method.
  • exhaust gas purification catalysts In order to remove harmful components such as hydrocarbon gas (HC), carbon monoxide (CO) and nitrogen oxide (NO) in exhaust gas from automobile engines, exhaust gas purification catalysts have been conventionally used. It has been used.
  • an exhaust gas purification catalyst a three-way catalyst that simultaneously purifies HC, CO, and NOx in exhaust gas burned at a stoichiometric air-fuel ratio is known.
  • a catalyst component made of a noble metal such as
  • JP-A-5-317652 discloses an exhaust gas purification catalyst in which an alkaline earth metal oxide and platinum are supported on a porous support.
  • JP-A-6-99069 disclosement 2
  • 1 to 20 g of palladium, 50 to 250 g of alumina, 50 to 250 g of alumina, and cerium oxide on the surface of the support substrate and the support substrate volume 11 are disclosed.
  • a catalyst component layer carrying 10 to 150 g of each catalyst component and 8 to 50 g of barium oxide, a catalyst for exhaust gas purification is disclosed.
  • JP-A-10-174866 Document 3
  • An exhaust gas purifying catalyst larger than the rhodium supported mass per unit mass of the carrier is disclosed.
  • At least one kind of rare earth element force that always contains a rare earth element and does not contain a rare earth element capable of taking a valence smaller than trivalent is selected.
  • An exhaust gas purifying catalyst is disclosed! Speak.
  • noble metals are dissolved in the perovskite structure and stable in an acid state, so that they are contained in the structure.
  • the precious metal used does not function as an active point of the catalyst, and the catalytic activity is not always sufficient.
  • An exhaust gas purifying catalyst in which a catalytically active component containing a zirconium oxide having one structure is coated on a refractory three-dimensional structure.
  • a catalytically active component containing a zirconium oxide having one structure is coated on a refractory three-dimensional structure.
  • ceria And noble metal supported on metal oxide particles containing zirconia and the metal oxide particles have a central portion containing more zirconia than ceria, and a surface layer containing more ceria than zirconia.
  • a purification catalyst is disclosed.
  • Japanese Patent Application Laid-Open No. 2004-243177 Document 9
  • at least CeO and ZrO are contained in one particle.
  • the noble metal is supported on the composite oxide powder using a noble metal salt aqueous solution having a pH value lower than the water immersion pH value when the complex oxide powder is suspended in pure water.
  • An exhaust gas purifying catalyst is disclosed.
  • Japanese Patent Laid-Open No. 7-75737 discloses a method for regenerating an exhaust gas purification catalyst in which a noble metal is supported as an active species on an inorganic porous base material, and halogen is added to the catalyst.
  • a method is disclosed in which a halogen is released from the halide after the precious metal halide is produced on the base material by the action.
  • JP 2000-202309 A discloses exhaust gas purification comprising a support containing at least one selected from alkaline earth metal oxides and rare earth oxides and platinum supported on the support.
  • a method is disclosed in which an oxidation treatment is performed on a catalyst for use, followed by a reduction treatment.
  • the method described in Document 11 is not necessarily sufficient in terms of shortening the time required for the regeneration treatment for regenerating the catalyst activity by redispersing the grown platinum particles and reducing the temperature. It was hard to do anything.
  • the present invention has been made in view of the above-described problems of the prior art and sufficiently suppresses the aggregation of noble metal particles even when exposed to high-temperature exhaust gas for a long time, thereby prolonging noble metal grain growth for a long period of time. It is possible to sufficiently suppress the decrease in catalytic activity, and to re-disperse the noble metal particles in a short time even in a relatively low temperature range when grains are grown during use.
  • the catalyst for exhaust gas purification that can easily regenerate the catalyst activity and can be easily regenerated even when it is attached to the exhaust system of the internal combustion engine, the regeneration method of the catalyst for exhaust gas purification, It is another object of the present invention to provide an exhaust gas purifying apparatus and an exhaust gas purifying method using the exhaust gas purifying catalyst.
  • the present inventors have found that a specific oxide having a surface oxide layer in which a noble metal is bonded to a cation of the carrier via oxygen on the surface of the carrier.
  • the catalyst surprisingly found that noble metal grain growth is sufficiently suppressed over a long period of time, and that it is possible to sufficiently suppress a decrease in catalyst activity, and when the noble metal is used to grow grains.
  • the present inventors have found that it is possible to efficiently regenerate the catalyst by subjecting such an exhaust gas purification catalyst to an oxidation treatment and a reduction treatment, thereby completing the present invention.
  • the exhaust gas purifying catalyst of the present invention is an exhaust gas purifying catalyst in which a noble metal is supported on an oxide carrier,
  • the carrier is loaded with a percentage of the amount of the noble metal that is present on the surface of the carrier in a metallic state and exposed on the surface of the carrier as measured by a CO chemisorption method. It is an exhaust gas purifying catalyst with an atomic ratio of 10% or more based on the total amount of noble metals.
  • the noble metal is at least one element selected from a group force including platinum, noradium, and rhodium force.
  • the bond energy value of Is orbital of oxygen in the carrier is 53 leV or less.
  • the electronegativity of at least one of the cations in the carrier is lower than the electronegativity of zirconium.
  • the carrier is selected from the group consisting of zirconia and Z or alumina, an alkaline earth metal element, a rare earth element, and a group 3A element.
  • the support contains zirconia and Z or alumina, and magnesium, calcium, barium, lanthanum, cerium, neodymium, prasedium, yttrium and Scandium force group force It is more preferable that it contains a complex oxide with at least one selected element.
  • the oxide carrier preferably the cation in the oxide carrier has an electronegativity lower than the electronegativity of zirconium and is in the acid carrier.
  • the oxygen orbital bond energy value of 531 eV or less shows an extremely strong interaction with noble metals.
  • the noble metal mediates oxygen on the surface of the support in an acid atmosphere. Then, the surface oxide layer as shown in FIG. 1 is formed by combining with the cation of the carrier.
  • the grain growth of the noble metal is sufficiently suppressed even when exposed to a high temperature exhaust gas for a long time. be able to. Furthermore, in the exhaust gas purifying catalyst of the present invention, in a reducing atmosphere, the noble metal is in a metallic state on the surface of the carrier and is exposed on the surface of the carrier measured by a CO chemical adsorption method. Since the ratio of the amount of precious metal is 10% or more in terms of atomic ratio with respect to the total amount of precious metal, the precious metal that is the active point of the catalyst is highly dispersed (highly dispersed as fine particles! In a stable state on the surface of the support and maintain high catalytic activity.
  • the catalyst for exhaust gas purification according to the present invention is used for a long period of time and grown, heating in an oxidizing atmosphere containing oxygen (preferably 500 to: heated at L000 ° C) Therefore, the noble metal exhibits a strong interaction at the interface with the support to form a surface oxide layer, and is gradually dispersed in a spread state on the support surface. As a result, the noble metal on the support is supported in a highly dispersed state in an oxide state (redispersion) in a relatively short time of oxidation treatment.
  • the present inventors infer that the noble metal in the oxide state is reduced to the metal state by performing the reduction treatment, and the catalytic activity is regenerated.
  • the exhaust gas purifying catalyst of the present invention more preferably satisfies the following condition (I).
  • the amount of the noble metal supported is in the range of 0.05 to 2% by mass with respect to the mass of the catalyst.
  • the amount of the additive component supported is such that the molar ratio of the noble metal to the amount of the noble metal (the amount of the additive component Z the amount of the noble metal) is in the range of 0.5 to 20.
  • the elements contained in the additive component are magnesium, calcium, neodymium, prasedium, barium, lanthanum, cerium, yttrium, and scandium power.
  • it further comprises iron carried on the carrier,
  • the supported amount of iron is such that the molar ratio of the amount of the precious metal to the amount of the precious metal (amount of iron Z amount of precious metal) is in the range of 0.8-12.
  • the exhaust gas purifying catalyst of the present invention satisfies the condition (I)
  • the occurrence of noble metal grain growth is more sufficiently suppressed over a long period of time. It has been found that the decrease in activity can be more sufficiently suppressed, and furthermore, by performing oxidation treatment and reduction treatment on such an exhaust gas purification catalyst, the time required for the regeneration treatment and the temperature can be reduced. It was found that the catalyst activity can be regenerated more efficiently.
  • the additive containing at least one additive element selected from the group power of alkaline earth metal element, rare earth element and group 3A element is supported on the carrier, the basicity of the carrier is improved.
  • the support exhibits a stronger interaction with the noble metal.
  • the exhaust gas purifying catalyst that satisfies the condition (I) can sufficiently suppress the growth of noble metal particles even when exposed to high-temperature exhaust gas for a long time, and more sufficiently suppress the decrease in catalytic activity. This comes out.
  • the exhaust gas purifying catalyst of the present invention is more preferably one that satisfies the following condition (i).
  • the amount of the noble metal supported is in the range of 0.05 to 2% by mass with respect to the mass of the catalyst.
  • the amount of iron supported is such that the molar ratio of the amount of the noble metal to the amount of the noble metal (amount of iron Z amount of noble metal) is in the range of 0.8-12.
  • the exhaust gas purifying catalyst of the present invention satisfies the condition ( ⁇ )
  • the inventors surprisingly suppressed the noble metal grain growth more sufficiently over a long period of time, and reduced the activity of the catalyst. It has been found that it is possible to more effectively regenerate the catalyst by subjecting such an exhaust gas purification catalyst to oxidation treatment and reduction treatment. .
  • an exhaust gas purifying catalyst that satisfies the condition (II)
  • a composite of zirconia and Z or alumina and at least one element selected from the group power of alkaline earth metal elements, rare earth elements, and group 3A elements is selected.
  • An oxide preferably, a complex oxide having a high electron density of oxygen and having a bond energy value of oxygen Is orbital of 531 eV or less
  • iron (Fe) is supported on a carrier containing such a complex oxide.
  • Such Fe is alloyed with a noble metal in a reducing atmosphere, and is deposited as an oxide on and around the surface of the noble metal in an oxidizing atmosphere. Therefore, by supporting Fe on the carrier, it is possible to more sufficiently suppress the noble metal grain growth in a fluctuating atmosphere when using the catalyst, and it is possible to more sufficiently suppress the decrease in the catalyst activity. Further, in such an exhaust gas purifying catalyst, since Fe exists in the vicinity of the noble metal, oxidation and reduction of the noble metal are facilitated, and the activity of the exhaust gas purifying reaction can be further improved. Especially adding Fe The reducibility is improved.
  • the carrier is a fluorite-type carrier comprising a complex acid salt of zirconium and at least one metal element selected from the group consisting of rare earth elements and alkaline earth metal elements and containing cerium;
  • the amount of the metal element contained in the support is in the range of 51 to 75 mol% in terms of metal with respect to the support, and the amount of cerium contained in the metal element is in terms of metal with respect to the metal element.
  • the amount of the noble metal supported per lOOg of the carrier is represented by the formula (1):
  • X represents a reference value (unit: g) of the amount of the noble metal per 100 g of the support
  • ⁇ represents the formula (2):
  • ⁇ represents the ratio (unit: mol%) of the metal element contained in the carrier.
  • Equation 1 s- ⁇ a 2 + ⁇ J ⁇ 2) xa 2 + ⁇ J ⁇ / 2) xa 2 ⁇ / 3 ⁇ 2 (3) [0035] (In equation (3), a is a lattice. Constant (unit: A)
  • N indicates the number of apogado (6.02X 10 23 (unit: piece))
  • M indicates the above-mentioned supported on the carrier
  • Precious metal Indicates atomic weight.
  • the inventors surprisingly have more sufficient grain growth of noble metal even when exposed to high-temperature exhaust gas for a long time.
  • the noble metal can be re-dispersed to easily regenerate and retain the catalytic activity. It has been found that the catalyst activity per unit amount of the noble metal can be sufficiently high to exhibit excellent catalyst activity.
  • the carrier has a fluorite structure and the ratio of cerium in the metal element is in the above range, cerium is used. Is present in a solid solution state in the carrier, the decrease in specific surface area is sufficiently suppressed even in a high-temperature atmosphere, and the number of sites capable of holding the noble metal per unit amount of the carrier is sufficient. The grain growth of the noble metal is sufficiently suppressed, and the decrease in the catalytic activity can be sufficiently suppressed. In addition, since the amount of the noble metal is in a range that satisfies the above-described conditions, grain growth caused by excess noble metal is suppressed.
  • the exhaust gas-purifying catalyst satisfying the condition (III) is used for a long period of time and grain growth is performed, heating is performed in an oxidizing atmosphere containing oxygen (preferably 500 to: heated at LOOO ° C).
  • an oxidizing atmosphere containing oxygen preferably 500 to: heated at LOOO ° C.
  • the noble metal forms a composite oxide and a metal oxide with the support, and is gradually dispersed in a state of spreading on the support surface.
  • the noble metal on the support is in a highly dispersed and supported state in the form of an oxide (redispersion), and then is subjected to a reduction treatment so that the noble metal is in an acidic state.
  • the present inventors infer that the noble metal is reduced to the metallic state, and the catalytic activity is regenerated.
  • the regeneration method of the exhaust gas purifying catalyst of the present invention is a method of subjecting the exhaust gas purifying catalyst of the present invention to an oxidation treatment and a reduction treatment in which heating is performed in an oxidizing atmosphere containing oxygen.
  • the temperature in the oxidation treatment is 500 to: LOOO ° C, and Z or GO has an oxygen concentration of 1 in the oxidizing atmosphere. It is preferable that it is volume% or more.
  • the oxidation treatment and the reduction treatment are performed in a state where the exhaust gas purification catalyst is mounted on an exhaust system of an internal combustion engine. it can.
  • a temperature sensor is attached to the exhaust gas purifying catalyst, and the operating time and the temperature detected by the temperature sensor are as follows. And a step of determining the degree of deterioration of the exhaust gas purification catalyst based on the above, and a step of starting the regeneration after it is determined that the catalyst is in a deteriorated state, and Z or Gv) using a catalyst deterioration diagnosis device for determining the deterioration state of the exhaust gas purification catalyst, and determining the deterioration state of the exhaust gas purification catalyst; and determining that the catalyst is in a deteriorated state And a step of starting the regeneration process later.
  • the first exhaust gas purification apparatus of the present invention comprises:
  • the exhaust gas purifying catalyst of the present invention disposed inside the exhaust gas supply pipe, a temperature sensor mounted on the exhaust gas purifying catalyst,
  • the degree of deterioration of the exhaust gas purifying catalyst is determined based on the operation time and the temperature detected by the temperature sensor. After the catalyst is determined to be in a deteriorated state, the catalyst is placed in an oxidizing atmosphere containing oxygen. Control means for controlling the oxidation treatment to be heated and the regeneration treatment for performing the reduction treatment to be started,
  • the exhaust gas purifying catalyst of the present invention disposed inside the exhaust gas supply pipe, a catalyst deterioration diagnosis device for determining the deterioration state of the exhaust gas purification catalyst, and the catalyst deterioration diagnosis device for exhaust gas purification
  • a control means for controlling the start of the regeneration process for performing the oxidation process and the reduction process for heating in an oxidizing atmosphere containing oxygen after the determination of the deterioration state of the catalyst;
  • the exhaust gas purification method of the present invention is a method for purifying exhaust gas by bringing the exhaust gas into contact with the exhaust gas purification catalyst of the present invention.
  • FIG. 1 is a schematic diagram showing a state of a surface oxide layer in which a noble metal is bonded to a cation of a carrier via oxygen on the surface of the carrier.
  • FIG. 5 is a graph showing a relationship between a reference value X of the amount of noble metal calculated by the equation (1).
  • the shaded area in Fig. 2 indicates the range of less than twice the reference value X and 0.01-0.8g.
  • FIG. 3 is a transmission electron microscope (TEM) photograph of the exhaust gas-purifying catalyst obtained in Example 1.
  • Fig. 4 shows a transmission electron microscope (TEM) image of the catalyst for exhaust gas purification obtained in Comparative Example 1. Is true.
  • FIG. 5 shows a Fourier transform of the EXAFS spectrum of the exhaust gas purification catalyst obtained in Example 1 and Comparative Example 1 and Pt oil and Pt L-edge of PtO powder for reference.
  • FIG. 6 is a graph showing a spectrum obtained by Fourier transforming the EXAFS spectrum of the exhaust gas purifying catalyst obtained in Example 2.
  • FIG. 7 is a graph showing a spectrum obtained by Fourier transforming the EXAFS spectrum of the exhaust gas purifying catalyst obtained in Example 3.
  • FIG. 8 is a graph showing a spectrum obtained by Fourier transforming the EXAFS spectrum of the exhaust gas purifying catalyst obtained in Example 5.
  • FIG. 9 is a graph showing a spectrum obtained by Fourier transforming the EXAFS spectrum of the exhaust gas purifying catalyst obtained in Example 7.
  • FIG. 10 is a graph showing the results of a platinum redispersion rate test.
  • the exhaust gas purifying catalyst of the present invention is a catalyst in which a noble metal is supported on an oxide carrier, and the noble metal is present in a highly oxidized state on the surface of the carrier in an oxidizing atmosphere.
  • the carrier In a reducing atmosphere, the carrier is loaded with a percentage of the amount of the noble metal that is present on the surface of the carrier in a metallic state and exposed on the surface of the carrier as measured by a CO chemisorption method.
  • the atomic ratio is 10% or more with respect to the total amount of noble metals.
  • the oxide support according to the present invention preferably has a value of 531 eV or less of the bond energy value of the oxygen Is orbital in the oxide support, and shows a value of 531 to 529 eV. It is particularly preferred that Acids with a binding energy value exceeding 531 eV When an object is used, the interaction between the noble metal and the support is not sufficiently strong, and the surface oxide layer of the noble metal and the support cannot be efficiently formed in an oxidizing atmosphere! It tends to be a habit. Furthermore, the precious metal on the support tends not to be sufficiently redispersed even after the oxidation treatment and reduction treatment described later.
  • Examples of the acid oxide carrier that satisfies such conditions include the following:
  • the electronegativity of at least one of the cations in the oxide support is lower than the electronegativity of the cation of zirconium. Is preferred. If the electronegativity of the cation in such an oxide carrier is higher than the electronegativity of the cation of zirconium, the interaction between the noble metal and the carrier will not be sufficiently strong, and the noble metal is not oxidized in an oxidizing atmosphere. It tends to be difficult to efficiently form a surface oxide layer between the support and the carrier, and the precious metal on the support is not sufficiently redispersed even after the oxidation treatment and reduction treatment described later. It is in.
  • an oxide support a complex acid of zirconia and Z or alumina and at least one element selected from the group power of an alkaline earth metal element, a rare earth element, and a group 3A element force is used. It is preferable to include a product.
  • alkaline earth metal elements include magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra). Mg, Ca, Ba are preferred because they have a strong action and tend to have a large affinity.
  • the rare earth elements and Group 3A elements include scandium (Sc), yttrium (Y), lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), samarium (Sm), and gadolinium (Ga). ), Terbium (Tb), dysprosium (Dy), ytterbium (Yb), lutetium (Lu), etc.
  • the interaction with noble metals and their oxides is strong and the affinity tends to be great! /
  • the view, force, La, Ce, Nd, Pr, Y, Sc force ⁇ preferably, La, Ce, Y, Nd power ⁇ Better than! / ⁇ .
  • rare earth elements and alkaline earth metal elements with low electronegativity have strong interaction with noble metals, they bind to noble metals through oxygen in an oxidizing atmosphere, and suppress transpiration and sintering of noble metals. Deterioration of the noble metal that is the active point can be sufficiently suppressed.
  • the above-described zircoure and Z or alumina are combined with at least one element selected from the group consisting of an alkaline earth metal element, a rare earth element and a group 3A element.
  • An acid must be formed. That is, a state in which zirconia and Z or alumina and at least one element selected from the group consisting of an alkaline earth metal element, a rare earth element, and a group 3A element coexist (for example, zirconia particles and Z or alumina).
  • Alumina particles, alkaline earth metal oxide particles, rare earth oxide particles, and group force of 3A group oxide particle force At least one selected oxide particle is uniformly dispersed! / In the state), when the regeneration treatment is performed, the precious metal on the support cannot be sufficiently redispersed, and the catalytic activity is not sufficiently restored (regenerated).
  • the ratio) is not particularly limited, but the ratio of zircoure and Z or alumina in the complex oxide is preferably 5 to 90% by mass, more preferably 10 to 70% by mass.
  • the ratio of zirconia and Z or alumina in the composite oxide is less than the above lower limit, the specific surface area becomes small and not only the grain growth of the noble metal particles can be sufficiently suppressed, but also the regeneration of the present invention described later.
  • Noble metal particles on the support do not tend to be sufficiently small even when the regeneration treatment is applied, and on the other hand, if the above upper limit is exceeded, the interaction between the noble metal and the support is insufficient, and noble metal grain growth occurs. In addition to not being able to sufficiently suppress this, noble metal particles on the support tend not to be sufficiently small even after regeneration treatment.
  • the oxide carrier may further contain alumina, zeolite, zirconium, etc. as other components in addition to the composite oxide described above.
  • the ratio of the complex oxide in the acid carrier according to the present invention is preferably 50% by mass or more.
  • the support according to the present invention includes a complex oxide of zirconium and at least one metal element selected from the group consisting of rare earth elements and alkaline earth metal elements and containing cerium, and fluorite. It is particularly preferable to have a mold structure.
  • the fluorite structure is one of the crystal structures of AX type compounds (A is a metal element and X is oxygen).
  • This is a structure represented by the formula, and is a face-centered cubic lattice with 4 chemical formulas in the unit cell.
  • the amount of the metal element contained in the carrier is preferably in the range of 51 to 75 mol% in terms of metal with respect to the carrier. Further, the amount of such a metal element is preferably in the range of 51.5 to 70 mol% in terms of metal with respect to the support, and more preferably in the range of 52 to 65 mol%. 52.5 is particularly preferably in the range of 5 to 60 mol%. If the amount of such a metal element is less than 51 mol%, the number of sites capable of holding the noble metal of the support is reduced, the noble metal cannot be efficiently held, and the regeneration method of the present invention described later is adopted. Thus, noble metal particles on the carrier tend not to be sufficiently small even when regenerated. On the other hand, if the amount of such a metal element exceeds 75 mol%, it is difficult to maintain the specific surface area because the zirconium ratio in the composite oxide is reduced, and the heat resistance tends to be inferior.
  • the amount of cerium contained in the metal element in such a carrier is in the range of 90 mol% or more in terms of metal with respect to the metal element.
  • the amount of cerium is less than 90 mol%, metal elements other than cerium cannot be completely dissolved in the support, and the specific surface area tends to be reduced.
  • zirconium and the metal element are in a solid solution and have a uniform composition in the particles.
  • CeO in the carrier is significantly
  • the shape of the acid oxide carrier according to the present invention is not particularly limited, but the specific surface area is not particularly limited. It is preferable to be in a powder form since higher catalytic activity can be obtained by improving.
  • the particle size (secondary particle size) of the carrier is not particularly limited, and is preferably 5 to 200 / ⁇ ⁇ . If the particle size is less than the lower limit, it is costly to make the carrier finer, and the handling tends to be difficult. On the other hand, if the particle size exceeds the upper limit, the exhaust gas purifying of the present invention is applied to a substrate as described later. It tends to be difficult to stably form the coating layer of the soot catalyst.
  • the specific surface area of such an oxide support is not particularly limited, but such a specific surface area can be calculated as a BET specific surface area using an adsorption isotherm force BET isotherm adsorption equation. I'll do it.
  • the specific surface area of such carriers, lm 2 is preferably at Zg more instrument 5 m 2 Zg more preferably is the following instrument 10 m 2 and more preferably is at Zg or instrument It is particularly preferably 15 m 2 Zg or more.
  • the specific surface area is less than the lower limit, it becomes difficult to support an appropriate amount of a noble metal in order to exhibit sufficient catalytic activity.
  • the specific surface area of the carrier is preferably larger, so the upper limit of the specific surface area is not particularly limited.
  • the carrier used for such a catalyst is: It is also possible to use a material whose specific surface area has been reduced by measuring the heat history in advance. Therefore, as a carrier according to the present invention, the specific surface area 80m less than 2 Zg added previously heat history, and further may be used that is less than 60 m 2 Zg. Such a specific surface area can also be calculated as the BET specific surface area by using the adsorption isotherm force and the BET isotherm adsorption equation.
  • the method for producing the carrier according to the present invention is not particularly limited, and can be obtained by the following method, for example. That is, the presence of ammonia from an aqueous solution containing a metal salt (for example, nitrate) as a raw material of the composite oxide and, if necessary, a surfactant (for example, a nonionic surfactant).
  • a metal salt for example, nitrate
  • a surfactant for example, a nonionic surfactant
  • a noble metal is supported on the carrier.
  • the examples of such noble metals include platinum, rhodium, palladium, osmium, iridium, gold, etc., but the viewpoint that the obtained exhaust gas purifying catalyst exhibits higher catalytic activity includes platinum, rhodium, noradium. From the viewpoint of the preferred regeneration, platinum and noradium are preferred.
  • the noble metal is present in a highly oxidized state on the surface of the support in an acid atmosphere, and the noble metal is on the surface of the support. It has a surface oxide layer formed by bonding with the cation of the carrier through oxygen. Therefore, in the exhaust gas purifying catalyst of the present invention, the noble metal that is an active point of the catalyst is present in a highly dispersed state on the surface of the support and is supported on the surface of the support in a stable state. Therefore, sufficiently high catalytic activity can be exhibited, and noble metal grain growth is sufficiently suppressed.
  • the “high acid state” in the present invention refers to a state where the noble metal is higher than zero.
  • the “acid atmosphere” here means an atmosphere of gas having an oxygen concentration of 0.5 volume% or more. Further, the acid state of the noble metal on the surface of the support and the bonding state with the support can be confirmed by TEM (transmission electron microscope) observation and XAFS (X-ray absorption fine structure) spectral analysis.
  • the amount of the noble metal present on the surface of the support measured by a CO chemical adsorption method in a reducing atmosphere is an atomic ratio of the support. It is 10% (more preferably 15%) or more with respect to the total amount of noble metal supported on the substrate. If the atomic ratio with respect to the amount of the noble metal present on the surface of the support is less than 10%, the dispersed state of the noble metal existing on the surface of the support becomes insufficient, and the catalytic activity per unit amount of the noble metal decreases. However, the catalyst activity tends to be difficult to regenerate by the regeneration treatment.
  • the method described in Japanese Patent Application Laid-Open No. 2004-340637 is adopted as such a CO chemisorption method.
  • the “reducing atmosphere” referred to here means an atmosphere of gas having a reducing gas concentration of 0.1% by volume or more.
  • the noble metal and a cation having an electronegativity lower than that of zirconium of the oxide exposed on the surface of the carrier is preferably 1.5 or more.
  • a part of the noble metal is responsible. It tends to be difficult to obtain interaction with the body.
  • the amount of the noble metal supported is 0.05 to 2% by mass (more preferably 0.1 to 0.5% by mass) with respect to the mass of the catalyst. ) Is preferable. If the amount of the noble metal supported is less than the lower limit, the catalytic activity obtained with the noble metal tends to be insufficient, while if the amount exceeds the upper limit, the cost tends to increase and grain growth tends to occur.
  • the amount of the noble metal supported per lOOg of the carrier is not more than twice the reference value X described below and 0.01-0.8g (more preferably 0.02). -0.5 g, more preferably 0.05-0.3 g).
  • the amount of the noble metal supported is less than the lower limit, the catalytic activity obtained by the noble metal tends to be insufficient.
  • the upper limit is exceeded, the cost increases and grain growth is likely to occur.
  • the catalytic activity per unit amount tends to decrease.
  • X represents a reference value (unit: g) of the amount of the noble metal per 100 g of the support
  • ⁇ represents the formula (2):
  • ⁇ represents the ratio (unit: mol%) of the metal element contained in the carrier.
  • a represents the lattice constant (unit: A)
  • N indicates the number of apogad (6.0.2 X 10 23 (unit: piece)), and M is supported on the carrier.
  • the supported amount of the noble metal per lOOg of the support is preferably 0.01 to 0.8 g and not more than twice the reference value X (more preferably 1.5 times, still more preferably 1 time).
  • the atomic weight M of the precious metal is the sum of all the values calculated by multiplying the atomic weight of each precious metal by the ratio of each precious metal to the total precious metal amount. To be calculated.
  • Such an expression (1) shows the amount of sites for stably holding the noble metal on the support, that is, the relationship between the reference value X of the noble metal and the composition and specific surface area of the support. . If the amount of noble metal supported exceeds twice the reference value X calculated by the above formula (1), the amount of noble metal supported will increase with respect to the amount of sites for supporting the noble metal. Precious metals exist, grain growth tends to occur, and the catalytic activity per unit amount of precious metals tends to decrease. However, when the loading amount of the noble metal is not more than twice the reference value X, the noble metal can be redispersed more easily by performing the regeneration treatment of the present invention described later. The catalyst activity per unit amount can be regenerated more efficiently.
  • the loading amount of the noble metal is close to the reference value X
  • the amount of the noble metal is close to the amount of the site for supporting the noble metal on the carrier, and the grain growth is further suppressed and the reproducibility tends to be improved.
  • the loading amount of the noble metal is equal to or less than the reference value X
  • FIG. 2 is a graph showing the relationship between the reference value X of the amount of noble metal in the above formula (1) and the specific surface area S of the support.
  • the amount of the precious metal supported per lOOg of the support is not more than twice the reference value X calculated by the above formula (1) and is in the range of 0.01 to 0.8 g.
  • rich gas CO (3.75 vol%) ZH (1.25 vol%) ZH0 (3 (Capacity%) Z N (balance)
  • lean gas O (5% by volume) ZH 0 (3% by volume) ZN (balance)
  • the noble metal is supported on a carrier in the form of finer particles U.
  • the particle size of such noble metal is more preferably 3 nm or less, and more preferably 2 nm or less. When the particle diameter of the noble metal exceeds the upper limit, it tends to be difficult to obtain high catalytic activity.
  • the method for supporting the noble metal on the carrier is not particularly limited except that the amount of the noble metal supported is adjusted so as to satisfy the above-mentioned conditions.
  • the amount of the noble metal supported is not limited to the above-mentioned conditions. It is possible to employ a method in which an aqueous solution containing a noble metal salt (for example, a dinitrodiammine salt) complex (for example, a tetraammine complex) prepared so as to satisfy the above conditions is contacted with the support, dried, and further calcined. .
  • a noble metal salt for example, a dinitrodiammine salt
  • a tetraammine complex for example, a tetraammine complex
  • an additive component containing at least one element selected from the group power consisting of alkaline earth metal element, rare earth element, and group 3A element power is provided on the support. It is preferable to carry more.
  • the basicity of the support can be further improved, and a stronger interaction can be imparted between the support and the noble metal supported on the support. Therefore, it becomes possible to sufficiently suppress the grain growth of the noble metal and sufficiently suppress the decrease in the catalytic activity.
  • an extremely strong interaction acts between the carrier and the noble metal as described above, and the grain growth of the noble metal tends to be suppressed. Even when it grows, it can regenerate the catalytic activity by redispersing the precious metal more efficiently in a short time by adopting the regeneration process of the catalyst for exhaust gas purification according to the present invention described later. .
  • the basicity of the carrier can be further improved to suppress the grain growth more sufficiently, and the catalytic activity can be facilitated even when the noble metal grain grows. From the point of view that it can be restored to magnesium, calcium, neodymium, praseodymium, norium, lanthanum, cerium, yttrium and scandium
  • the group power of Muka is more preferable neodymium, barium, yttrium and scandium in which at least one selected element is preferred.
  • any element containing the above element is sufficient.
  • the element itself, an oxide of the element, a salt of the element (carbonate, nitrate, citrate, acetate, sulfate) ) And their mixtures.
  • the supported amount of such an additive component is such that the molar ratio (amount of additive component Z amount of noble metal) to the amount of the noble metal in terms of metal is 0.5 to 20 (preferably 1 to 10). This is an amount in the range of. If such a molar ratio is less than the lower limit, it is difficult to improve the basicity of the carrier because the loading amount of the additive component is not sufficient, and the effect of more sufficiently suppressing the noble metal grain growth tends to be reduced. On the other hand, if the upper limit is exceeded, the specific surface area of the support tends to decrease, and the dispersibility of the noble metal tends to decrease.
  • the amount of the additive component supported is such that the additive component is 1.28 X 10_6 to 1.28 X 10_3 mol per lg of the support 5. 13 X 10 _6 ⁇ 5.1 More preferable amount to be 1 3 X 10 _4 mol 5. More preferable to be 13 X 10 _6 ⁇ 2.56 X 10 _4 mol 5 . it is especially preferred 13 X 10 one 6-1 is the amount of the 28 X 10 _4 mol.
  • the carrier is supported at a high density near the outer surface of the carrier. In such a state, when the carrier is in the form of a powder, 80% or more of the additive component is 30% from the outer surface of the carrier between the outer surface force of the carrier and the center of the carrier. It is preferable to be carried in the area of%.
  • the method for supporting the additive component on the carrier is not particularly limited, and includes, for example, a salt of the above element (for example, carbonate, nitrate, acetate, citrate, sulfate) or a complex. It is possible to employ a method in which the aqueous solution to be dried is brought into contact with the carrier and then dried and further baked. Further, if necessary, the support may be preheated and stabilized, and then the additive may be supported. In addition, when supporting such an additional component, the order in which the additional component and the noble metal are supported on the support is not particularly limited. [0086] In the exhaust gas purifying catalyst of the present invention, it is preferable that iron is further supported on the carrier.
  • Fe is alloyed with a noble metal in a reducing atmosphere, while Fe precipitates on the surface and the periphery of the noble metal as an oxide in an acidic atmosphere.
  • the grain growth of the noble metal can be more sufficiently suppressed, the decrease in the catalyst activity can be more sufficiently suppressed, and further, the regeneration treatment adopting the regeneration method of the exhaust gas purifying catalyst of the present invention described later is performed.
  • the precious metal particles which are active sites, tend to be further refined to sufficiently regenerate the catalyst activity.
  • the amount of iron supported is such that the molar ratio (the amount of iron Z the amount of noble metal) to the amount of the noble metal in terms of metal is 0.5 to 12 (more preferably 0.8 to 12, more preferably Is preferably in the range of 1 to 10, particularly preferably 1 to 5). If the molar ratio is less than the lower limit, the amount of iron supported is small and the effect of suppressing the growth of noble metal grains tends to be insufficient, and if the upper limit is exceeded, excessively supported iron is not supported. The catalytic activity tends to decrease because the specific evaluation area of the metal is reduced and the surface of the noble metal is covered after long-term use.
  • the upper limit of the above molar ratio is particularly preferably 1.5, more preferably 1.5 from the viewpoint of reduction in the specific surface area of the support and coating of the noble metal surface.
  • the lower limit of the amount of iron supported is preferably an amount of 1.28 X 10 " 4 mol per lOOg of the support 2. 0.5 X 10 _4 mol It is more preferable that the amount is 4.10 X 10 _4 mol, and it is even more preferable that the amount is 5.13 X 10 _4 mol.
  • the upper limit of the amount is preferably 1.23 X 10 _1 mol per 100 g of the carrier. 5. 13 X 10 _2 mol is more preferable 3. 10 X 10 more preferably that amount which becomes _2 mol device 1. it is particularly preferred is an amount which is a 28 X 10 _2 mol,.
  • the state of the iron supported on the carrier is not particularly limited, but the iron is preferably supported closer to the noble metal. .
  • the effect of suppressing the grain growth of the noble metal tends to be further improved, and the regeneration treatment adopting the regeneration method for the exhaust gas purifying catalyst of the present invention described later is employed.
  • the precious metal that is the active site The catalyst activity tends to be regenerated.
  • the method for supporting such iron is not particularly limited, and for example, an aqueous solution containing an iron salt (for example, carbonate, nitrate, acetate, citrate, sulfate) or a complex. It is possible to employ a method of drying after further contact with the above-mentioned carrier and further firing. In addition, such iron loading may be performed simultaneously with the noble metal. For example, after bringing a mixed solution of an aqueous solution of a noble metal salt and an aqueous solution of an iron salt into contact with the support, drying and further firing. Can be adopted. Further, if necessary, the support may be supported by heat treatment and then the iron or precious metal may be supported.
  • an iron salt for example, carbonate, nitrate, acetate, citrate, sulfate
  • a complex for example, an iron salt (for example, carbonate, nitrate, acetate, citrate, sulfate) or a complex. It is possible to employ a method of drying after further contact with
  • the exhaust gas purifying catalyst of the present invention comprises the support, the noble metal supported on the support, and the iron supported on the support
  • the catalyst is supported on the support.
  • the supported state of the noble metal and the iron is not particularly limited, but it is preferable that the iron is supported closer to the noble metal.
  • the form of the exhaust gas purifying catalyst of the present invention is not particularly limited, and may be a form such as a Hercum-shaped monolithic catalyst or a pellet-shaped pellet catalyst.
  • the base material used here is not particularly limited and is appropriately selected according to the use of the obtained catalyst, etc., but a DPF base material, a monolithic base material, a pellet base material, a plate base material, etc. are suitably employed. Is done.
  • the material of such a base material is not particularly limited, but a base material made of ceramics such as cordierite, carbide, mullite, or a base material made of metal such as stainless steel containing chromium and aluminum is preferable. Adopted.
  • the method for producing such a catalyst is not particularly limited.
  • the above-mentioned carrier is formed on a heart-shaped substrate formed from cordierite or metal foil.
  • a method of forming a coat layer made of the above powder and supporting a noble metal thereon is preferably employed.
  • the above-mentioned carrier powder may be preliminarily supported with a noble metal, and the noble metal-supported powder may be used to form a coat layer on the substrate.
  • an exhaust gas purifying catalyst of the present invention it is supported on a carrier after being used for a long time.
  • the precious metal particles can be refined (redispersed) by regenerating the exhaust gas purifying catalyst of the present invention, which will be described later, to sufficiently regenerate the catalytic activity.
  • the particle size of the noble metal supported on the support after such regeneration treatment is preferably 3 nm or less (more preferably 2 nm or less) from the viewpoint of obtaining high catalytic activity. ,.
  • the exhaust gas purifying catalyst of the present invention has been described above. Hereinafter, the regeneration method of the exhaust gas purifying catalyst of the present invention will be described.
  • the method for regenerating an exhaust gas purifying catalyst of the present invention is characterized in that the exhaust gas purifying catalyst of the present invention is subjected to an oxidation treatment and a reduction treatment that are heated in an oxidizing atmosphere containing oxygen. It is a method to do.
  • the oxidizing atmosphere in which the oxidation treatment according to the present invention is performed can oxidize a noble metal corresponding to the number of moles if oxygen is contained even a little, but the concentration of oxygen is 0.5. It is preferably 1% by volume or more and more preferably 1% by volume or more. If the oxygen concentration is less than the lower limit, the redispersion of the noble metal on the support tends not to proceed sufficiently. On the other hand, the higher the oxygen concentration, the better from the viewpoint of acidity, but the oxygen concentration in the air In order to exceed 20% by volume, a special device such as an oxygen cylinder is required, and the cost tends to increase. Further, as the gas other than oxygen in the oxidizing atmosphere according to the present invention, it is preferable to use nitrogen gas or inert gas which preferably does not contain a reducing gas.
  • the heating temperature in the acid soot treatment which is useful in the present invention, is supported! Any temperature at which the noble metal is oxidized may be used, but a temperature in the range of 500 to 1000 ° C is preferred. If the oxidation treatment temperature is less than 500 ° C, the rate of redispersion of the noble metal on the support tends to be extremely slow and does not proceed sufficiently.On the other hand, if it exceeds 1000 ° C, the support itself tends to contract by heat. Thus, the catalytic activity tends to decrease.
  • the time required for the oxidation treatment according to the present invention is appropriately selected according to the oxidation treatment temperature and the like, and it takes a long time if the temperature is low, and it may be short if the temperature is high.
  • the time per oxidation treatment step is preferably about 1 second to 1 hour. If the oxidation time is less than 1 second, the noble metal on the support There is a tendency that the redispersion of the metal does not proceed sufficiently, and on the other hand, the redispersion action of the noble metal tends to be saturated after 1 hour.
  • the oxidation treatment according to the present invention may be performed in a predetermined processing apparatus after the exhaust gas purification catalyst is taken out from the exhaust system, but is performed in a state where it is mounted on the exhaust system of the internal combustion engine. It is preferable. As a result, it is possible to greatly reduce the number of man-hours for the oxidation treatment, and it is possible to reduce the precious metal oxides by circulating the exhaust gas after the oxidation treatment.
  • oxidation is performed with the exhaust gas purification catalyst attached to the exhaust system in this way, for example, a large amount of air is introduced from an air valve provided upstream of the catalyst, or the air-fuel ratio (AZF) of the mixture is increased.
  • the fuel supply amount can be significantly reduced to increase the air-fuel ratio (A ZF) of the air-fuel mixture.
  • the catalyst may be heated by a specific heating device, or may be heated using the heat of reaction on the catalyst.
  • the oxidation treatment can be performed in real time in accordance with the degree of deterioration of the catalyst performance.
  • the acid treatment may be performed periodically according to the driving time or mileage of the car, or the catalyst performance is detected by installing a NOx sensor or CO sensor downstream of the catalyst, and that value is the reference value. If it exceeds the limit, it may be acidified.
  • the reduction treatment according to the present invention can be carried out by heating the catalyst in an atmosphere in which a reducing gas such as hydrogen or carbon monoxide is present. Therefore, the engine exhaust as a whole contains a reducing gas even in a stoichiometric atmosphere, so that noble metals can be sufficiently reduced. Further, in the reduction treatment, it is sufficient that the reducing gas is contained even a little, but the concentration of the reducing gas is preferably 0.1% by volume or more. When the concentration of the reducing gas is less than the lower limit, the noble metal on the support tends to hardly return to an active state. Further, as the gas other than the reducing gas in the reducing atmosphere which is useful in the present invention, it is preferable to use nitrogen gas or inert gas which preferably does not contain oxidizing gas.
  • the heating temperature in the reduction treatment according to the present invention may be a temperature at which the noble metal oxides oxidized by the oxidation treatment are reduced, but is preferably 200 ° C or higher.
  • the temperature is preferably in the range of 400 to 1000 ° C.
  • the reduction temperature is less than 200 ° C In this case, the precious metal oxides on the support tend not to be sufficiently reduced.
  • the upper limit is exceeded, thermal contraction of the support itself tends to occur and the catalytic activity tends to decrease.
  • the time required for the reduction treatment according to the present invention is appropriately selected according to the reduction treatment temperature and the like, and it is necessary for a long time if the temperature is low, and may be short if the temperature is high. .
  • the reduction treatment temperature is 200 ° C or higher
  • the time per reduction treatment step is preferably about 2 seconds to 5 minutes.
  • the reduction treatment time is less than the lower limit, the noble metal acid hydrate on the support tends not to be sufficiently reduced.
  • the upper limit is exceeded, the reduction action of the noble metal oxide tends to be saturated.
  • the reduction treatment according to the present invention may be performed in a predetermined processing apparatus after the exhaust gas purifying catalyst is taken out from the exhaust system, but may be implemented in a state of being mounted on the exhaust system of the internal combustion engine. It is preferable. As a result, the number of reduction treatment steps can be greatly reduced, and the precious metal oxides can be reduced simply by circulating the exhaust gas after the oxidation treatment. In this way, when the exhaust gas purification catalyst is attached to the exhaust system, for example, in the case of an automobile exhaust gas purification catalyst, a stoichiometric or oxygen stoichiometric ratio or oxygen It is preferable to carry out by bringing the exhaust gas in a rich atmosphere lacking in contact with the exhaust gas purification catalyst.
  • the oxidation treatment and the reduction treatment can be performed while the exhaust gas purification catalyst is attached to the exhaust system, and the regeneration treatment of the present invention can be performed as part of the air-fuel ratio control.
  • the heating means the catalyst may be heated by a specific heating device, or may be heated using the heat of the exhaust gas.
  • the oxidation treatment and the reduction treatment are each in one step, the power that the reduction treatment is performed after the oxidation treatment.
  • the oxidation treatment and the reduction treatment are alternately performed. In that case, the oxidation treatment may be performed first or the reduction treatment may be performed first. Further, when the oxidation treatment and the reduction treatment are alternately repeated, the difference between the total time of the former treatment and the total time of the latter treatment is not particularly limited!
  • a temperature sensor is attached to the exhaust gas purifying catalyst, and based on the operation time and the temperature detected by the temperature sensor! / A step (I) of determining the degree of deterioration of the exhaust gas-purifying catalyst;
  • the regeneration process can be performed while confirming the deterioration state of the exhaust gas-purifying catalyst, so that the catalyst can be regenerated more efficiently.
  • the first exhaust gas purification apparatus of the present invention is provided with a control means for controlling so as to start an oxidation treatment for heating in an atmosphere and a regeneration treatment for performing a reduction treatment. Can be used.
  • Such a temperature sensor is not particularly limited, and a known temperature sensor that can detect the temperature state of the exhaust gas purifying catalyst can be appropriately used.
  • the control means includes, for example, an engine control unit (ECU).
  • the method for determining the degree of deterioration is not particularly limited.
  • a map of the relationship between the operating time and temperature until the deterioration state that requires regeneration processing is measured in advance, and based on that map, the specific operating time at a specific temperature
  • a method of determining that the catalyst has deteriorated when the catalyst is used can be adopted. The degree of deterioration is determined in this way, and the regeneration process is started after determining that the catalyst is in a deteriorated state.
  • the regeneration process is controlled so that the regeneration process is started when the temperature of the exhaust gas purifying catalyst is in the range of 500 to: LOOO ° C. It is preferable to apply treatment. By controlling the reproduction process in this way, it becomes possible to perform a more efficient reproduction process.
  • the regeneration treatment is performed to perform the regeneration treatment according to the relationship between the degree of deterioration of the exhaust gas purification catalyst and the temperature of the regeneration treatment. Determine the time required to fully regenerate the catalyst, It is preferable to control the time for applying the reduction process. By performing the regeneration process in this way, unnecessary heating time and the like can be reduced, and the catalyst can be regenerated more efficiently. In such control, the above-described control means can be used. Further, the method for determining the time required for sufficiently regenerating the exhaust gas purification catalyst by performing the regeneration process is not particularly limited, but the time necessary for the regeneration process at a specific temperature is measured in advance. A method of creating a map of the relationship between the time required for the playback process and the temperature at that time and determining the time required for the playback process based on the map can be mentioned.
  • the deterioration state of the exhaust gas purifying catalyst is determined using a catalyst deterioration diagnosis device for determining the deterioration state of the exhaust gas purifying catalyst.
  • the exhaust gas supply pipe and any one of claims 1 to 7 disposed inside the exhaust gas supply pipe The exhaust gas purifying catalyst according to any one of claims 1, a catalyst deterioration diagnosis device for determining a deterioration state of the exhaust gas purification catalyst, and the deterioration state of the exhaust gas purification catalyst were determined by the catalyst deterioration diagnosis device.
  • a second exhaust gas purifying apparatus according to the present invention comprising a control means for controlling so that an oxidation process for heating in an oxidizing atmosphere containing oxygen and a regeneration process for performing a reduction process are started later. It can be used suitably.
  • the method for regenerating an exhaust gas purifying catalyst of the present invention uses a catalyst deterioration diagnosis device for determining the deterioration state of the exhaust gas purifying catalyst instead of the step (I).
  • the regeneration process can be performed in the same manner as in the regeneration method including the above-described process (I) and process (II) except that the process of determining the deterioration state of the exhaust gas purification catalyst is employed.
  • Such a catalyst deterioration diagnosis device is not particularly limited as long as it is a device capable of determining the deterioration state of the exhaust gas purifying catalyst.
  • the control means includes, for example, an engine control unit (ECU).
  • ECU engine control unit
  • the power described above for the regeneration method of the exhaust gas purifying catalyst of the present invention is 3 nm or less. (More preferably 2 nm or less) can be refined (redispersed). Then, by performing such a regeneration treatment and refining (redispersing) the noble metal particles to the particle size supported on the carrier, the catalyst activity can be more fully regenerated.
  • the exhaust gas purification method of the present invention is a method characterized by purifying exhaust gas by bringing the exhaust gas into contact with the exhaust gas purification catalyst of the present invention.
  • Such an exhaust gas purification method is not particularly limited except that the exhaust gas purifying catalyst of the present invention is used to bring the exhaust gas into contact with the exhaust gas purifying catalyst of the present invention.
  • the method for bringing the exhaust gas into contact with the exhaust gas purification catalyst is not particularly limited, and a known method can be appropriately employed.
  • Aqueous cerium nitrate solution (Contains 28 wt% as CeO) 242.6 g, Zirconium oxynitrate
  • Anhydrous solution (containing 18 wt 0/0 as ZrO) 157. 6 g, yttrium nitrate 12. 6 g and Nonio
  • aqueous surfactant manufactured by Lion Corporation, trade name: Leocon
  • 142 g of 25 wt% ammonia water was added to 2000 g of a mixed aqueous solution containing 10 g, and the mixture was stirred at room temperature for 10 minutes to obtain a coprecipitate.
  • the obtained coprecipitate was filtered, washed, dried at 110 ° C, and further calcined in the atmosphere at 100 ° C for 5 hours to cerium-zirconium yttrium complex oxide (CeO-ZrO-).
  • CeO-ZrO- cerium-zirconium yttrium complex oxide
  • a carrier consisting of Y ⁇ was obtained.
  • the composition ratio of the obtained composite oxide was 55m
  • the value of the combined energy of the s orbit was determined by XPS (X-ray photoelectron spectroscopy), and the values shown in Table 4 were obtained.
  • the amount of platinum supported in the medium was 1% by weight.
  • the platinum catalyst in the obtained catalyst Table 1 shows the ratio (MsZPGM) of cation (PGM) and cation mole (Ms) having a lower electronegativity than zirconium in the complex oxides exposed on the surface of the carrier.
  • MsZPGM such a ratio
  • MsZPGM the value of such a ratio
  • a ratio 1.54 ⁇ 10 _5 mol of cation exists on the outermost surface per specific surface area lm 2 of the support. If the proportion of cations having a lower electronegativity than zirconium is X%, 1.54 X 10 " 5 XX / lOOmol is present on the outermost surface of the carrier and the electronegativity of zirconium per lm 2 of the specific surface area of the carrier.
  • the number of moles of cations (Ms) of the cation having a lower electrical anionicity, and the number of moles of noble metal per lm 2 of the specific surface area of the carrier is given by the following formula:
  • Y indicates the number of moles of the noble metal
  • W indicates the weight ratio of the noble metal to the support (unit: wt%)
  • S indicates the specific surface area of the support (unit m 2 Zg)
  • M indicates the atomic weight of the noble metal.
  • Aqueous zirconium nitrate solution (containing 18% by weight as ZrO) 231g and lanthanum nitrate
  • composition ratio was 65 wt% ZrO and 35 wt% La 2 O.
  • above complex oxide was 65 wt% ZrO and 35 wt% La 2 O.
  • Table 1 shows the MsZPGM values.
  • Example 3 A cerium-zirconium yttrium composite oxide (CeO-ZrO-YO, composition ratio: 55 mol%) obtained by adopting the same method as the carrier production method adopted in Example 1
  • the amount of platinum supported on the catalyst was 0.5 wt%, the amount of Ba per lg of support was 0.00000128 mol, and the molar ratio of Pt to Ba (Ba / Pt) was 5.
  • Tables 1 and 3 show the values of Ms ZPGM in the obtained catalyst.
  • An exhaust gas purifying catalyst of the present invention was obtained in the same manner as in Example 3 except that 5.62 g of neodymium nitrate hexahydrate was added instead of barium nitrate.
  • Table 3 shows the value of MsZPG M in the obtained catalyst.
  • the catalyst for exhaust gas purification of the present invention was obtained in the same manner as in Example 3 except that a palladium nitrate aqueous solution (Pd concentration: 4% by weight) was used instead of a dinitrodiamineplatinum nitric acid aqueous solution (Pt concentration: 4% by weight). It was.
  • Tables 1 and 3 show the value of MsZPGM in the obtained catalyst.
  • the catalyst for exhaust gas purification of the present invention was obtained in the same manner as in Example 4 except that a palladium nitrate aqueous solution (Pd concentration: 4% by weight) was used instead of an aqueous solution of dinitrodiammine nitrate in nitric acid (Pt concentration: 4% by weight). It was.
  • Table 3 shows the MsZPGM values for the obtained catalyst.
  • a catalyst for purification of exhaust gas according to the present invention was obtained in the same manner as in Example 3 except that an aqueous rhodium nitrate solution (Rh concentration: 4% by weight) was used instead of an aqueous nitric acid solution of dinitrodiamine platinum (Pt concentration: 4% by weight). It was.
  • Tables 1 and 3 show the value of MsZPGM in the obtained catalyst.
  • Example 8 A catalyst for purification of exhaust gas according to the present invention was obtained in the same manner as in Example 4 except that an aqueous rhodium nitrate solution (Rh concentration: 4 wt%) was used instead of an aqueous nitric acid solution of dinitrodiammine platinum (Pt concentration: 4 wt%). It was. In addition, Table 3 shows the MsZPGM values for the obtained catalyst.
  • MsZPGM The values of MsZPGM are shown in Tables 1 and 3.
  • Comparative Example 1 except that commercially available SiO powder (manufactured by Aerosil Co., Ltd.) was used as the carrier.
  • a catalyst for purifying exhaust gas for comparison was obtained in the same manner as in Comparative Example 1 except that an aqueous solution of palladium nitrate (Pd concentration: 4 wt%) was used instead of an aqueous nitric acid solution of dinitrodiamine platinum (Pt concentration: 4 wt%).
  • Pd concentration: 4 wt% an aqueous solution of palladium nitrate
  • Pt concentration: 4 wt%) aqueous nitric acid solution of dinitrodiamine platinum
  • a catalyst for purification of exhaust gas for comparison was obtained in the same manner as in Comparative Example 1 except that an aqueous rhodium nitrate solution (Rh concentration: 4 wt%) was used instead of an aqueous nitric acid solution of dinitrodiammine platinum (Pt concentration: 4 wt%). It was.
  • Table 3 shows the MsZPGM values for the obtained catalyst.
  • Each catalyst was subjected to an acid treatment at 1000 ° C. for 5 hours in an acid atmosphere having a volume of 0% by volume). Then, TEM (Transmission Electron Microscopy) observation was performed on each of the catalysts obtained in Example 1 and Comparative Example 1 after such oxidation treatment. In addition, for each of the catalysts obtained in Examples 1 to 3, 5, and 7 and Comparative Example 1 after such acid and sour treatment, XAFS (X-ray Absorption) of noble metals (Pt, Pd, Rh) was used. Fine Structure) Measurements were made to analyze the local structure around the noble metal, and the state of the noble metal on the support was observed. The obtained TEM photographs are shown in Fig. 3 (Example 1) and Fig.
  • Rh / Ba / Zr l.33
  • the dispersibility value of the exhaust gas purification catalyst for comparison is as low as 2%.
  • the dispersibility value was very high at 20% or more, and in the exhaust gas purifying catalyst of the present invention, noble metal was present. It was confirmed to exist with high dispersion.
  • the noble metal exists in a highly oxidized state on the surface of the support in an oxidizing atmosphere, and the noble metal is Bonding with the cation of the composite oxide via oxygen exposed on the surface of the carrier, forming a surface oxide layer of the noble metal and the carrier, and in a reducing atmosphere, It was confirmed that the noble metal exists in a highly dispersed metal state.
  • Example 3 8 and Comparative Example 1 3 4 were used, and each was compacted at a pressure of ltZcm 2 by employing the cold isostatic pressing method (CIP method). Thereafter, 0.5 to: pulverized to a size of Lmm to obtain a pellet-shaped catalyst.
  • each pellet-shaped catalyst obtained in this way is charged into a reaction vessel, and the rich gas and lean gas shown in Table 2 are added to the reaction vessel so that the flow rate per 3 g of catalyst is 500 ccZ. Exchange every minute
  • the precious metal particles on the support were grown by flowing into each other and treating at 950 ° C for 5 hours (endurance test).
  • the average particle size of the noble metal particles after such an endurance test was determined, and the results obtained are shown in Table 3.
  • the average particle diameter of the noble metal particles was determined by the CO chemical adsorption method described in Japanese Patent Application Laid-Open No. 2004-340637.
  • the platinum on the carrier was grown by heat treatment at 1000 ° C. for 5 hours. And for the catalyst with platinum grown in this way, O 20 volume ° / ( ⁇ N 80 volume%
  • an oxidation treatment (redispersion treatment) was performed at 800 ° C for 30 minutes, and platinum was redispersed.
  • Table 4 shows the average particle size of the platinum particles after the durability test and the average particle size of the platinum particles after the redispersion treatment.
  • the average particle size of the platinum particles was determined by the CO chemical adsorption method described in JP 2004-340637 A.
  • oxidation treatment and reduction treatment for each exhaust gas purification catalyst were realized, and this was designated as regeneration treatment.
  • an oxidation treatment (redispersion treatment) for 10 seconds at 700 ° C was alternately repeated over 100 minutes to attempt redispersion of platinum.
  • Pt L3-edge XANES X-ray Absorption Near Edge Spectra
  • the average particle diameter of platinum particles is determined from the height of the peak called white-line in the XANES spectrum. Estimates and changes over time in the average particle size of the platinum particles during the treatment were examined. The obtained results are shown in FIG.
  • a platinum redispersion rate test was conducted in the same manner as in Test Example 6 except that the treatment temperature in the treatment of alternately repeating the reduction treatment and the oxidation treatment was 600 ° C.
  • Figure 10 shows the results obtained.
  • the redispersion of platinum proceeds by alternately repeating the reduction treatment and the oxidation treatment.
  • the average particle diameter of platinum particles is small up to 3.6 nm in Test Example 6 and up to 2.9 nm in Example 7. Kunatsuta.
  • the redispersion rate of platinum was faster at 700 ° C than at a processing temperature of 600 ° C.
  • the regeneration process of the present invention is part of the air-fuel ratio control. And can be efficiently regenerated in a state where the catalyst is mounted on the exhaust system of the internal combustion engine. Therefore, according to the regeneration method of the present invention, it was confirmed that high catalytic activity without requiring special maintenance can be maintained for a long time.
  • Aqueous cerium nitrate solution (containing 28 mass as CeO 0/0) 233g, Okishi zirconium nitrate
  • a carrier composed of ZrO—Y 2 O 3) was obtained.
  • the composition ratio of the obtained complex oxide (CZY) is
  • the bond energy values of the oxygen Is orbitals were determined by XPS (X-ray photoelectron Spectros copy), and the values shown in Table 5 were obtained.
  • the obtained additive-supported carrier was immersed in a nitric acid aqueous solution of dinitrodiammine platinum (platinum concentration: 4% by mass), filtered and washed, and then dried at a temperature of 110 ° C.
  • the catalyst for exhaust gas purification of the present invention in the form of powder was obtained by calcining in the atmosphere at a temperature of 500 ° C. for 3 hours to support the carrier with additional components containing Pt and Ba.
  • the powdery exhaust gas purifying catalyst of the present invention employs a cold isostatic pressurization method (CIP method).
  • the powder After compacting at a pressure of ltZcm 2 , the powder was pulverized to a size of 0.5 to Lmm to obtain a pellet-shaped catalyst.
  • the supported amount of Pt was 0.5% by mass
  • the supported amount of Ba in the additive component was 0.000128 mol per lg of the carrier.
  • the molar ratio (BaZPt) of the amount of Ba in the soot component was 5.
  • a pellet-shaped catalyst for exhaust gas purification of the present invention was obtained in the same manner as in Example 9 except that 5.62 g of neodymium nitrate hexahydrate was added instead of barium nitrate.
  • the amounts of Pt and Ba supported on the obtained exhaust gas purification catalyst are shown in Table 5.
  • a pellet-shaped catalyst for exhaust gas purification of the present invention was obtained in the same manner as in Example 9 except that the amount of barium nitrate added was changed to 0.677 g.
  • Table 5 shows the supported amounts of Pt and Ba in the obtained exhaust gas purification catalyst.
  • a pellet-shaped catalyst for exhaust gas purification of the present invention was obtained in the same manner as in Example 9 except that the amount of barium nitrate added was changed to 1.35 g.
  • the amounts of Pt and Ba supported on the obtained exhaust gas purification catalyst are shown in Table 5.
  • a pellet-shaped catalyst for exhaust gas purification of the present invention was obtained in the same manner as in Example 9 except that the amount of barium nitrate added was changed to 6.77 g.
  • the amounts of Pt and Ba supported on the obtained exhaust gas purification catalyst are shown in Table 5.
  • a pellet-shaped exhaust gas purification catalyst of the present invention was obtained in the same manner as in Example 9 except that the amount of barium nitrate added was changed to 0.677 g, and 1.05 g of iron nitrate was further added to the mixed solution. .
  • Table 5 shows the supported amounts of Pt, Ba and Fe in the obtained exhaust gas purification catalyst.
  • a pellet-like composition of the present invention was prepared in the same manner as in Example 14 except that the mixed amount of dinitrodiamineplatinic acid in nitric acid was added to a mixed solution of barium nitrate and iron nitrate, and Pt, Ba, and Fe were simultaneously supported.
  • An exhaust gas purifying catalyst was obtained.
  • Table 5 shows the supported amounts of Pt, Ba, and Fe.
  • a pellet-shaped exhaust gas purifying catalyst of the present invention was obtained in the same manner as in Example 12 except that the calcination temperature condition for obtaining the support was changed from 1000 ° C to 700 ° C.
  • the amounts of Pt and Ba supported on the exhaust gas purification catalyst obtained are shown in Table 5.
  • a catalyst for purification of exhaust gas for comparison was manufactured using the same carrier as that used in Example 9. That is, the carrier lOOg was immersed in an aqueous nitric acid solution of dinitrodiammine platinum (platinum concentration: 4 mass%), filtered, washed, dried at a temperature of 110 ° C, and further dried in the atmosphere at a temperature of 500 ° C for 3 hours. The exhaust gas-purifying catalyst for comparison in powder form with Pt supported on the carrier was obtained. The amount of platinum supported on the obtained catalyst was 0.5% by mass.
  • the exhaust gas purifying catalyst thus obtained was compacted at a pressure of ltZcm 2 by adopting a cold isostatic pressing method (C IP method), and 0.5 to Lmm To give a pellet-shaped catalyst.
  • Table 5 shows the amount of Pt supported in the obtained exhaust gas purification catalyst.
  • Example 17 Same as Example 17 except that a commercially available ⁇ -Al powder (Grace) was used as the carrier.
  • a commercially available ⁇ -Al powder (Grace) was used as the carrier.
  • Oxidation treatment (redispersion treatment) was performed for 30 minutes, and redispersion of the noble metal was attempted.
  • Table 5 shows the average particle size of the precious metal particles of each exhaust gas purification catalyst after such redispersion treatment.
  • the average particle size of the noble metal was determined by the CO chemical adsorption method described in JP-A-2004-340637. By such redispersion treatment and reduction pretreatment by the CO chemical adsorption method, oxidation treatment and reduction treatment for each exhaust gas purification catalyst were realized, and this was designated as regeneration treatment.
  • Aqueous cerium nitrate solution (contains 28% by mass as CeO) 242.6 g, zirconium nitrate
  • Anhydrous solution (containing 18 mass 0/0 as ZrO) 157. 6 g, yttrium nitrate 12. 6 g and Bruno - O
  • the obtained additive-supported support was immersed in a nitric acid aqueous solution of platinum (platinum concentration: 4% by mass), filtered and washed, and then dried at a temperature of 110 ° C. Calcination was performed in the atmosphere at 500 ° C. for 3 hours to obtain a powdery exhaust gas purifying catalyst of the present invention in which Pt and Fe were supported on the carrier.
  • the powdery exhaust gas purifying catalyst of the present invention thus obtained is compacted at a pressure of ltZcm 2 using the cold isostatic pressing method (CIP method), and 0.5 to:
  • the catalyst was pulverized to a size of Lmm to obtain a pellet-shaped catalyst.
  • the supported amount of Pt was 1% by mass
  • the supported amount of Fe was 0.0000513 mol per 100 g of the support
  • the molar ratio of the amount of Pt and the amount of Fe ( Fe / Pt) was 1 in terms of metal.
  • Example 19 A pellet-shaped exhaust gas purification catalyst of the present invention was obtained in the same manner as in Example 1 except that the amount of iron nitrate added was changed to 1.046 g and the amount of Pt supported was changed to 0.5% by mass. .
  • Table 8 shows the supported amounts of Pt and Fe and the molar ratio of Fe and Pt in the obtained exhaust gas purification catalyst.
  • a pellet-shaped catalyst for exhaust gas purification of the present invention was obtained in the same manner as in Example 19 except that the amount of iron nitrate added was changed to 2.092 g.
  • Table 8 shows the supported amounts of Pt and Fe and the molar ratio of Fe and Pt in the obtained exhaust gas purification catalyst.
  • a pellet-shaped catalyst for exhaust gas purification according to the present invention was obtained in the same manner as in Example 19 except that the amount of iron nitrate added was changed to 5.229 g.
  • Table 8 shows the supported amounts of Pt and Fe and the molar ratio of Fe and Pt in the obtained exhaust gas purification catalyst.
  • the present invention in the form of a pellet in which a loaded component containing Ba element was further loaded in the same manner as in Example 19 except that the amount of iron nitrate added was changed to 1.046 g and barium nitrate was further changed to 0.677 g.
  • the catalyst for exhaust gas purification was obtained.
  • Table 8 shows the amounts of Pt, Fe and Ba supported on the obtained exhaust gas purification catalyst.
  • a catalyst for exhaust gas purification according to the present invention in the form of pellets further carrying a supported component containing Ba element was added in the same manner as in Example 22 except that a nitric acid solution of dinitrodiammine platinum was also added in addition to iron nitrate and barium nitrate. Obtained.
  • Table 8 shows the supported amounts of Pt, Fe and Ba in the obtained exhaust gas purification catalyst.
  • a catalyst for exhaust gas purification for comparison was produced using the same carrier as that used in Example 18. That is, the carrier lOOg was immersed in an aqueous nitric acid solution of dinitrodiammine platinum (platinum concentration: 4% by mass), filtered, washed, dried at a temperature of 110 ° C, and further dried for 3 hours at a temperature of 500 ° C.
  • the catalyst for exhaust gas purification for comparison in the form of powder with Pt supported on the carrier was obtained by calcination in the medium. The amount of Pt supported in the obtained catalyst is 1% by mass. I got it.
  • the exhaust gas purification catalyst for comparison obtained in this way was subjected to compaction molding at a pressure of ltZcm 2 by adopting the cold isostatic pressurization method (CIP method), and then 0.5.
  • CIP method cold isostatic pressurization method
  • ⁇ The catalyst was pulverized to a size of Lmm to obtain a pellet-shaped catalyst.
  • a pellet-shaped exhaust gas purification catalyst of the present invention was obtained in the same manner as in Example 24 except that the supported amount of Pt was changed to 0.5% by mass.
  • Table 8 shows the amount of Pt supported in the obtained exhaust gas purification catalyst.
  • Exhaust gas purification catalysts for comparison in pellet form were obtained in the same manner as in Example 19 except that the amount of iron nitrate added was changed to 0.523 g.
  • Table 8 shows the supported amounts of Pt and Fe and the molar ratio of Fe and Pt in the obtained exhaust gas purification catalyst.
  • Exhaust gas purification catalysts for comparison in pellet form were obtained in the same manner as in Example 19 except that the amount of iron nitrate added was changed to 15.69 g.
  • Table 8 shows the supported amounts of Pt and Fe and the molar ratio of Fe and Pt in the obtained exhaust gas purification catalyst.
  • Durability test (I) was carried out using the pellet-shaped catalysts obtained in Examples 18 and 24, respectively. That is, in a gas atmosphere that has both H (3% by volume) and N (97% by volume), 95
  • Pt on the support was grown by treatment at 0 ° C for 10 hours (endurance test (1)).
  • the average particle diameter of Pt after such an endurance test was determined, and the results obtained are shown in Tables 6 and 7.
  • the average particle size of Pt was determined by the X-ray diffraction method (XRD) and the CO chemisorption method described in JP-A-2004-340637.
  • Table 6 shows the average particle size determined by XRD
  • Table 7 shows the average particle size determined by the CO chemisorption method.
  • Example 1 CZY Pt 1 F ⁇ 0. 00513 1 4. 8 Example 2 4 CZY Pt 1 None 0 0 6. 2
  • Table 7 shows the average Pt particle size of each exhaust gas purification catalyst after such redispersion treatment.
  • the average particle size of Pt was determined by the CO chemical adsorption method described in JP-A-2004-340637. By such redispersion treatment and reduction pretreatment by the CO chemical adsorption method, oxidation treatment and reduction treatment for each exhaust gas purification catalyst were realized, and this was designated as regeneration treatment.
  • the catalyst of Example 18 had a finer Pt particle size than the catalyst of Example 24, but this resulted in the precipitation of alloyed active-site strength iron oxide, This is because the amount of CO adsorbed increased due to the appearance of the Pt surface. From these results, it was confirmed that in the catalyst obtained in Example 18, Pt grain growth was suppressed in a rich atmosphere, and the active sites were regenerated by further regeneration treatment.
  • Table 8 shows the average Pt particle size of each exhaust gas purification catalyst after such redispersion treatment.
  • the average particle size of Pt was determined by the CO chemical adsorption method described in JP-A-2004-340637. By such redispersion treatment and reduction pretreatment by the CO chemical adsorption method, oxidation treatment and reduction treatment for each exhaust gas purification catalyst were realized, and this was designated as regeneration treatment.
  • the exhaust gas purification of the present invention obtained in Examples 19 to 23 in which the molar ratio of Fe to Pt (FeZPt) is in the range of 0.8 to 12 is shown.
  • the soot catalyst is an exhaust gas purification catalyst obtained in Example 25 in which the value of FeZPt is 0 and in Examples 26 to 27 in which the value of FeZPt is outside the range of 0 ⁇ 8 to 12. It was confirmed that the grain growth of Pt after the rich-lean endurance test was suppressed. Further, in the exhaust gas purifying catalyst of the present invention (Examples 19 to 23), the Pt particle diameter after regeneration treatment is weak, so that the catalyst activity can be sufficiently regenerated and a high catalyst activity can be obtained.
  • cerium-zirconium-praseodymium-lanthanum complex oxide (Ce 2 O 3 —ZrO—Pr 2 O 3 —La 2 O 3) was produced as a carrier.
  • non-ionic surfactant Lion Corporation, trade name: Leocon
  • the lattice constant of the carrier was 5.304A.
  • the exhaust gas purifying catalyst of the present invention was manufactured by supporting a noble metal on the carrier.
  • nitric acid aqueous solution of dinitrodiammine platinum (platinum concentration: 4 wt%) in 200 ml of ion-exchanged water was mixed in with 625 g, and 25 g of the carrier obtained as described above was mixed and impregnated.
  • the catalyst for exhaust gas purification according to the present invention Pt (0. lg) / CeO—ZrO—Pr O—La O (100 g) is fired in the atmosphere at 500 ° C. for 3 hours. Obtained.
  • cerium-zirconium-praseodymium-yttrium complex oxide (CeO—ZrO—PrO—YO) was produced as a carrier. That is, first, 28 wt% cerium nitrate
  • non-ionic surfactant Lion Corporation, trade name: Leocon
  • the obtained support precursor is dried at 110 ° C and then calcined in the atmosphere at 1000 ° C for 5 hours to obtain a cerite-zirconium-praseodymium-yttrium complex oxide strength structure.
  • Carrier composition ratio: 53mol% CeO, 44mol% ZrO, 0.5mol% PrO, lmol
  • the lattice constant of the resulting support was 5.304A.
  • an exhaust gas purification catalyst of the present invention was produced by supporting a noble metal on the carrier.
  • nitric acid aqueous solution of dinitrodiammine platinum in 200 ml of ion-exchanged water (platinum concentration: 4% by weight) 1.
  • cerium-zirconium composite oxide (CeO 2 -ZrO 2) was produced as a carrier.
  • the lattice constant of the obtained carrier was 5.334A.
  • an exhaust gas purification catalyst of the present invention was produced by supporting a noble metal on the carrier.
  • Impregnation was carried out by adding 25 g of the carrier obtained as described above to a mixture of 563 g. Thereafter, it was fired in the atmosphere at 500 ° C. for 3 hours to obtain the exhaust gas purifying catalyst of the present invention (Pt (0.25 g) / CeO—ZrO (100 g)).
  • cerium-zirconium-yttrium composite oxide (CeO -ZrO-
  • the lattice constant of the carrier was 5.305A.
  • an exhaust gas purification catalyst of the present invention was produced by supporting a noble metal on the carrier. That is, first, 25 g of the carrier obtained as described above was impregnated and supported in a mixed solution obtained by mixing 0.169 g of barium nitrate with 200 ml of ion-exchanged water, and then in the atmosphere. The catalyst precursor was obtained by calcination at 500 ° C. for 5 hours. Next, after adding 563 g of nitric acid aqueous solution of platinum dinitrodiamine (platinum concentration: 4 wt%) to 200 ml of ion-exchanged water, 25 g of the catalyst precursor was added and impregnated and supported in the atmosphere. Baked at 500 ° C for 3 hours The exhaust gas purifying catalyst (Pt (0.5 g) / CeO—ZrO—YO—BaO (lOOg)) of the present invention
  • Exhaust gas purifying catalyst (Pt (0.5 g) / CeO-ZrO—YO—) of the present invention in the same manner as in Example 31 except that the amount of barium nitrate mixed in the mixed solution was changed to 0.338 g.
  • Exhaust gas purification catalyst (Pt) of the present invention was prepared in the same manner as in Example 28 except that the amount of nitric acid aqueous solution (platinum concentration: 4% by weight) of dinitrodiammine platinum mixed in the mixed solution was changed to 3.125 g. (0.5 g) / CeO 2 —ZrO—Pr 2 O 3 —La 2 O (100 g)) was obtained.
  • Exhaust gas purification catalyst (Pt) for comparison in the same manner as in Example 28, except that the amount of nitric acid aqueous solution (platinum concentration: 4% by weight) of dinitrodiammine platinum mixed in the mixed solution was changed to 6.25 g. (lg) ZCeO—ZrO—Pr O—La O (100 g)) was obtained.
  • Exhaust gas purification catalyst Pt (0.25 g) / CeO-ZrO (100 g)
  • a non-ionic surfactant was used. It was.
  • Table 10 shows the results obtained.
  • the ratio (VZX) of the supported amount of Pt to the reference value X obtained by calculating the above equation (4) of the exhaust gas purifying catalyst of the present invention (Examples 28 to 30) is about It was 0.59 (Example 28), about 1.23 (Example 29), and about 0.51 (Example 30).
  • the exhaust gas purification catalysts obtained in Examples 34 to 35 were about 5.58 (Example 34) and about 7.50 times (Example 35), respectively.
  • Table 10 shows.
  • the propylene 50% purification temperature shown in Table 10 is a guideline for the performance of the three-way catalyst, and the lower the temperature, the higher the activity of the catalyst.
  • the exhaust gas purifying catalysts obtained in Examples 28, 29, and 31 to 33 can suppress the Pt grain growth after the endurance test! confirmed. Further, in the exhaust gas purifying catalysts obtained in Examples 28, 29 and 31 to 33, the activity per unit amount (specific activity) of Pt was as high as 0.17 or more even after the endurance test. Furthermore, it was confirmed that the Pt particle size was refined by the regeneration process, and the specific activity was regenerated to near 0.4. On the other hand, in the exhaust gas purifying catalyst obtained in Example 34, it was confirmed that noble metal grains grew and the specific activity decreased to 0.1 or less. Further, it was confirmed that the specific activity was not regenerated so much even after the regeneration treatment.
  • the exhaust gas purifying catalyst obtained in Examples 31 and 32 was obtained by supporting a noble metal after supporting a barrier which is an alkaline earth metal on the support surface. It was confirmed that the grain growth of Pt was further suppressed. These results are presumed to be due to the improvement of the basicity of the support by the addition of barium.
  • the ratio of the supported amount V of Pt to the reference value X obtained by calculating equation (4) in Table 11 (VZX) is the actual value because the amount of barium supported on the carrier is calculated as uniform over the entire Balta. It can be inferred that it is caused by being smaller than the above.
  • Example 33 Also in the exhaust gas purifying catalyst obtained in Example 33, it was confirmed that Pt grain growth was suppressed, and that the specific activity was regenerated by refining Pt by regenerating treatment. In Examples 31 and 32, In the obtained exhaust gas purification catalyst, it was confirmed that these effects were more remarkable.
  • noble metal particle aggregation can be sufficiently suppressed over a long period of time even when exposed to high-temperature exhaust gas for a long time, and thereby, noble metal particle growth can be sufficiently suppressed over a long period of time.
  • the precious metal particles when the grains grow during use, the precious metal particles can be re-dispersed in a short time even in a relatively low temperature range, and the catalyst activity can be easily regenerated.
  • an exhaust gas purifying catalyst that can be easily regenerated even when it is attached to the exhaust system of an internal combustion engine, a method for regenerating the exhaust gas purifying catalyst, and an exhaust gas purifying catalyst are provided. It is possible to provide the exhaust gas purification device and the exhaust gas purification method used.
  • the present invention provides HC, CO, NOx in exhaust gas that also emits automobile engine power. It is very useful as a technique for using an exhaust gas purifying catalyst for removing harmful components such as these without causing deterioration of catalytic activity over a long period of time.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Combustion & Propulsion (AREA)
  • Biomedical Technology (AREA)
  • Health & Medical Sciences (AREA)
  • Environmental & Geological Engineering (AREA)
  • Analytical Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Sustainable Development (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Catalysts (AREA)

Abstract

La présente invention concerne un catalyseur de purification de gaz d'échappement comprenant un métal noble porté sur un support d'oxyde, où : sous une atmosphère oxydante, le métal noble existe dans l'état d'oxydation le plus élevé sur la surface du support et le catalyseur possède une couche d'oxyde en surface formé par le métal noble liant un cation dans le support par l'intermédiaire de l'oxygène sur la surface du support ; tandis que sous une atmosphère réductrice, le métal noble existe dans un état métallique sur la surface du support et la quantité du métal noble exposée sur la surface du support, qui est mesurée par le procédé d'absorption chimique de CO, est supérieure ou égale à 10 % atomique sur la base de la quantité totale de métal noble portée par le support.
PCT/JP2006/324068 2006-03-28 2006-12-01 Catalyseur de purification de gaz d'echappement, son procede de regeneration, appareil de purification de gaz d'echappement l'utilisant et procede de purification de gaz d'echappement WO2007111004A1 (fr)

Priority Applications (6)

Application Number Priority Date Filing Date Title
CNA2006800541044A CN101415490A (zh) 2006-03-28 2006-12-01 废气净化用催化剂、该催化剂的再生方法、以及使用该催化剂的废气净化用设备和方法
CA2648314A CA2648314C (fr) 2006-03-28 2006-12-01 Catalyseur pour purification des gaz d'echappement, methode de regeneration pour le catalyseur, et appareil et methode pour purification des gaz d'echappement au moyen du catalyseur
BRPI0621483-5A BRPI0621483A2 (pt) 2006-03-28 2006-12-01 catalisador para purificação de gás exaurido, método de regeneração para o catalisador, e mecanismo e método para a purificação de gás exaurido utilizando o catalisador
EP06823547A EP2000202A4 (fr) 2006-03-28 2006-12-01 Catalyseur de purification de gaz d'echappement, son procede de regeneration, appareil de purification de gaz d'echappement l'utilisant et procede de purification de gaz d'echappement
US12/225,692 US8105561B2 (en) 2006-03-28 2006-12-01 Catalyst for purification of exhaust gas, regeneration method for the catalyst, and apparatus and method for purification of exhaust gas using the catalyst
ZA2008/09153A ZA200809153B (en) 2006-03-28 2008-10-27 Catalyst for purification of exhaust gas,regeneration method for the catalyst,and apparatus and method for purification of exhaust gas using the catalyst

Applications Claiming Priority (8)

Application Number Priority Date Filing Date Title
JP2006089120A JP4775953B2 (ja) 2006-03-28 2006-03-28 排ガス浄化用触媒及びその再生方法
JP2006-089177 2006-03-28
JP2006-089120 2006-03-28
JP2006089177A JP4775954B2 (ja) 2006-03-28 2006-03-28 排ガス浄化用触媒及びその再生方法
JP2006089186 2006-03-28
JP2006-089193 2006-03-28
JP2006089193 2006-03-28
JP2006-089186 2006-03-28

Publications (1)

Publication Number Publication Date
WO2007111004A1 true WO2007111004A1 (fr) 2007-10-04

Family

ID=38540939

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2006/324068 WO2007111004A1 (fr) 2006-03-28 2006-12-01 Catalyseur de purification de gaz d'echappement, son procede de regeneration, appareil de purification de gaz d'echappement l'utilisant et procede de purification de gaz d'echappement

Country Status (8)

Country Link
US (1) US8105561B2 (fr)
EP (2) EP2527033A1 (fr)
KR (1) KR100973378B1 (fr)
CN (1) CN101415490A (fr)
BR (1) BRPI0621483A2 (fr)
CA (1) CA2648314C (fr)
WO (1) WO2007111004A1 (fr)
ZA (1) ZA200809153B (fr)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009118189A1 (fr) * 2008-03-27 2009-10-01 Umicore Ag & Co. Kg Échange basique pour des matériaux de stockage d'oxygène (os) redox évolués destinés à des applications de contrôle des émissions
WO2012137930A1 (fr) * 2011-04-08 2012-10-11 トヨタ自動車株式会社 Catalyseur d'oxydation pour la purification de gaz d'échappement
US20120264597A1 (en) * 2009-07-20 2012-10-18 Council Of Scientific & Industrial Research CEAlO3 PEROVSKITES CONTAINING TRANSITION METAL
RU2468862C1 (ru) * 2008-11-21 2012-12-10 Ниссан Мотор Ко., Лтд. Очищающий от дисперсных частиц материал, фильтр-катализатор для очистки от дисперсных частиц с использованием очищающего от дисперсных частиц материала и способ регенерирования фильтра-катализатора для очистки от дисперсных частиц
US8778831B2 (en) 2008-03-27 2014-07-15 Umicore Ag & Co. Kg Base metal and base metal modified diesel oxidation catalysts
US9403151B2 (en) 2009-01-30 2016-08-02 Umicore Ag & Co. Kg Basic exchange for enhanced redox OS materials for emission control applications
WO2017130623A1 (fr) * 2016-01-28 2017-08-03 株式会社キャタラー OXYDE COMPOSITE À BASE DE Zr SUPPORTANT Pd
EP2276701A4 (fr) * 2008-03-27 2017-11-08 Umicore AG & Co. KG Métal commun et catalyseur d'oxydation du diesel modifié par un métal commun
CN107638787A (zh) * 2017-10-17 2018-01-30 东方电气集团东方锅炉股份有限公司 一种脱除气体中氮氧化物的系统和方法
RU225095U1 (ru) * 2023-12-15 2024-04-12 Денис Сергеевич Сугатов Трехмаршрутный автомобильный катализатор, содержащий редкоземельный металл Европий, и способ его получения

Families Citing this family (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2457901C2 (ru) * 2008-03-19 2012-08-10 АйСиТи КО., ЛТД. Катализатор для очистки выхлопного газа двигателя внутреннего сгорания и способ очистки выхлопного газа с использованием указанного катализатора
FR2939695B1 (fr) * 2008-12-17 2011-12-30 Saint Gobain Ct Recherches Structure de purification incorporant un systeme de catalyse supporte par une zircone a l'etat reduit.
US8227373B1 (en) * 2009-01-30 2012-07-24 The University Of Toledo Exhaust gas purification catalysts and methods of making the same
KR101430606B1 (ko) 2009-07-09 2014-08-14 도요타 지도샤（주） 배기 가스 정화 촉매 및 그 제조 방법
US8530372B2 (en) * 2009-07-22 2013-09-10 Basf Corporation Oxygen storage catalyst with decreased ceria reduction temperature
US9115621B2 (en) 2011-03-04 2015-08-25 Toyota Jidosha Kabushiki Kaisha Metal particles, exhaust gas purifying catalyst comprising metal particles, and methods for producing them
EP2749352B1 (fr) * 2011-08-23 2019-11-06 Toyota Jidosha Kabushiki Kaisha Catalyseur d'épuration de gaz d'échappement et son procédé de production
KR101305632B1 (ko) * 2011-09-21 2013-09-09 기아자동차주식회사 배기정화장치의 피독감지시스템 및 감지방법
JP5576420B2 (ja) * 2012-03-21 2014-08-20 トヨタ自動車株式会社 排ガス浄化触媒
US8765085B2 (en) * 2012-04-26 2014-07-01 Basf Corporation Base metal catalyst and method of using same
CN104602809B (zh) * 2012-06-20 2016-08-31 丰田自动车株式会社 用于净化废气的催化剂载体、使用该催化剂载体的用于净化废气的催化剂及生产该用于净化废气的催化剂载体的方法
CN103566951B (zh) * 2012-07-24 2015-10-28 上海纳米技术及应用国家工程研究中心有限公司 一种常温一氧化碳催化氧化失活催化剂的再生方法
US9266092B2 (en) 2013-01-24 2016-02-23 Basf Corporation Automotive catalyst composites having a two-metal layer
JP5942893B2 (ja) 2013-02-21 2016-06-29 マツダ株式会社 排気ガス浄化用触媒の製造方法
CN105658328A (zh) * 2013-11-20 2016-06-08 马自达汽车株式会社 尾气净化用催化剂及其制备方法
KR101600958B1 (ko) * 2014-04-28 2016-03-08 희성촉매 주식회사 압축천연가스 자동차 배기가스 산화촉매 재생방법
US9475004B2 (en) * 2014-06-06 2016-10-25 Clean Diesel Technologies, Inc. Rhodium-iron catalysts
JP6133836B2 (ja) * 2014-12-12 2017-05-24 トヨタ自動車株式会社 排ガス浄化触媒
JP6727235B2 (ja) * 2016-01-26 2020-07-22 新日本電工株式会社 セリア・ジルコニア系複合酸化物酸素吸放出材料、排ガス浄化触媒、及び排ガス浄化用ハニカム構造体
US10035133B2 (en) * 2016-10-25 2018-07-31 GM Global Technology Operations LLC Catalysts with atomically dispersed platinum group metal complexes and a barrier disposed between the complexes
WO2018095882A1 (fr) 2016-11-22 2018-05-31 Umicore Ag & Co. Kg Catalyseur contenant du fer
US10184374B2 (en) 2017-02-21 2019-01-22 Umicore Ag & Co. Kg Apparatus and method for desulfation of a catalyst used in a lean burn methane source fueled combustion system
CN110917869B (zh) * 2018-09-20 2022-09-06 中国石油化工股份有限公司 一种降低催化裂化过程中不完全再生烟气中NOx排放量的方法
CN109173727B (zh) * 2018-10-31 2021-09-24 攀钢集团攀枝花钢铁研究院有限公司 失效络合脱硝剂再生的方法
CN112684832B (zh) * 2019-10-17 2022-01-28 中国石油化工股份有限公司 克服碳化硅环状载体温度反应滞后的方法及设备
CN113457674B (zh) * 2021-05-31 2022-12-27 广西科技大学 一种提高Pt-CeO2催化剂氧化反应低温活性和耐久性的方法
CN116351461A (zh) * 2023-04-11 2023-06-30 浙江大学 一种高性能VOCs氧化降解Pt/CeO2-ZrO2-La2O3+ZSM-5催化剂的制备方法

Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH05317652A (ja) 1992-05-22 1993-12-03 Toyota Motor Corp 排気ガスの浄化方法
JPH0699069A (ja) 1992-09-18 1994-04-12 Cataler Kogyo Kk 排気ガス浄化用触媒
JPH0775737A (ja) 1993-07-08 1995-03-20 Mazda Motor Corp 排気ガス浄化用触媒の再生方法
JPH10174866A (ja) 1996-12-19 1998-06-30 Toyota Central Res & Dev Lab Inc 排ガス浄化用触媒
JPH1113458A (ja) * 1997-06-27 1999-01-19 Toyota Motor Corp 内燃機関の触媒状態検出装置
JP2000202309A (ja) 1999-01-18 2000-07-25 Toyota Central Res & Dev Lab Inc 排ガス浄化用触媒の再生方法
JP2002079053A (ja) 2000-06-27 2002-03-19 Ict:Kk 排気ガス浄化用触媒
JP2003220336A (ja) 2002-01-29 2003-08-05 Toyota Motor Corp 排ガス浄化用触媒
JP2004041866A (ja) 2002-07-09 2004-02-12 Daihatsu Motor Co Ltd 排ガス浄化用触媒
JP2004141833A (ja) 2002-10-28 2004-05-20 Toyota Motor Corp 金属酸化物粒子の製造法及び排ガス浄化用触媒
JP2004243177A (ja) 2003-02-12 2004-09-02 Toyota Motor Corp 排ガス浄化用触媒
JP2004340637A (ja) 2003-05-13 2004-12-02 Toyota Central Res & Dev Lab Inc 貴金属の分散性測定方法及び分散性測定装置
JP2005180201A (ja) 2003-12-16 2005-07-07 Toyota Motor Corp 内燃機関の触媒劣化診断装置
JP2005270882A (ja) 2004-03-25 2005-10-06 Tanaka Kikinzoku Kogyo Kk 触媒
JP2006055748A (ja) * 2004-08-20 2006-03-02 Tanaka Kikinzoku Kogyo Kk 触媒の製造方法
JP2006346587A (ja) * 2005-06-16 2006-12-28 Cataler Corp 排ガス浄化用触媒

Family Cites Families (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2690661B2 (ja) * 1991-06-10 1997-12-10 株式会社日本触媒 排気ガス浄化用触媒およびこれを用いてなる浄化システム
JP3473295B2 (ja) 1995-11-16 2003-12-02 株式会社豊田中央研究所 触媒担体及び排ガス浄化用触媒
EP1066874B1 (fr) * 1999-07-09 2009-09-23 Nissan Motor Company, Limited Catalyseur pour la purification de gaz d'échappement et procédé pour sa fabrication
JP4655436B2 (ja) 2001-08-31 2011-03-23 株式会社豊田中央研究所 排ガス浄化用触媒の処理方法
JP2003126694A (ja) 2001-10-25 2003-05-07 Toyota Motor Corp 排ガス浄化用触媒
JP2003245553A (ja) 2002-02-22 2003-09-02 Suzuki Motor Corp 触媒粉末及び排気ガス浄化触媒
JP2005023830A (ja) 2003-07-01 2005-01-27 Sumitomo Electric Ind Ltd 耐摩摺動部品
JP4329432B2 (ja) * 2003-07-15 2009-09-09 トヨタ自動車株式会社 排ガス浄化用触媒
EP1732679B1 (fr) * 2003-12-05 2012-03-07 Intercat, Inc. Procédé pour la réduction des émissions de SOx, NOx et CO dans un gaz
JP2006021141A (ja) 2004-07-08 2006-01-26 Nissan Motor Co Ltd 排ガス浄化用触媒及びその調製方法
DE602005016520D1 (de) 2004-07-22 2009-10-22 Toyota Motor Co Ltd Anorganisches oxid, abgasreinigungskatalysatorträger und abgasreinigungskatalysator
US20060217263A1 (en) * 2005-03-24 2006-09-28 Tokyo Roki Co., Ltd Exhaust gas purification catalyst
JP2007301526A (ja) * 2006-05-15 2007-11-22 Toyota Central Res & Dev Lab Inc 排ガス浄化用触媒及びその製造方法

Patent Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH05317652A (ja) 1992-05-22 1993-12-03 Toyota Motor Corp 排気ガスの浄化方法
JPH0699069A (ja) 1992-09-18 1994-04-12 Cataler Kogyo Kk 排気ガス浄化用触媒
JPH0775737A (ja) 1993-07-08 1995-03-20 Mazda Motor Corp 排気ガス浄化用触媒の再生方法
JPH10174866A (ja) 1996-12-19 1998-06-30 Toyota Central Res & Dev Lab Inc 排ガス浄化用触媒
JPH1113458A (ja) * 1997-06-27 1999-01-19 Toyota Motor Corp 内燃機関の触媒状態検出装置
JP2000202309A (ja) 1999-01-18 2000-07-25 Toyota Central Res & Dev Lab Inc 排ガス浄化用触媒の再生方法
JP2002079053A (ja) 2000-06-27 2002-03-19 Ict:Kk 排気ガス浄化用触媒
JP2003220336A (ja) 2002-01-29 2003-08-05 Toyota Motor Corp 排ガス浄化用触媒
JP2004041866A (ja) 2002-07-09 2004-02-12 Daihatsu Motor Co Ltd 排ガス浄化用触媒
JP2004141833A (ja) 2002-10-28 2004-05-20 Toyota Motor Corp 金属酸化物粒子の製造法及び排ガス浄化用触媒
JP2004243177A (ja) 2003-02-12 2004-09-02 Toyota Motor Corp 排ガス浄化用触媒
JP2004340637A (ja) 2003-05-13 2004-12-02 Toyota Central Res & Dev Lab Inc 貴金属の分散性測定方法及び分散性測定装置
JP2005180201A (ja) 2003-12-16 2005-07-07 Toyota Motor Corp 内燃機関の触媒劣化診断装置
JP2005270882A (ja) 2004-03-25 2005-10-06 Tanaka Kikinzoku Kogyo Kk 触媒
JP2006055748A (ja) * 2004-08-20 2006-03-02 Tanaka Kikinzoku Kogyo Kk 触媒の製造方法
JP2006346587A (ja) * 2005-06-16 2006-12-28 Cataler Corp 排ガス浄化用触媒

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP2000202A4

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2276701A4 (fr) * 2008-03-27 2017-11-08 Umicore AG & Co. KG Métal commun et catalyseur d'oxydation du diesel modifié par un métal commun
WO2009118189A1 (fr) * 2008-03-27 2009-10-01 Umicore Ag & Co. Kg Échange basique pour des matériaux de stockage d'oxygène (os) redox évolués destinés à des applications de contrôle des émissions
US8778831B2 (en) 2008-03-27 2014-07-15 Umicore Ag & Co. Kg Base metal and base metal modified diesel oxidation catalysts
US9222382B2 (en) 2008-11-21 2015-12-29 Nissan Motor Co., Ltd. Particulate matter purifying material, filter catalyst for purifying particulate matter using particulate matter purifying material, and method of regenerating filter catalyst for purifying particulate matter
RU2468862C1 (ru) * 2008-11-21 2012-12-10 Ниссан Мотор Ко., Лтд. Очищающий от дисперсных частиц материал, фильтр-катализатор для очистки от дисперсных частиц с использованием очищающего от дисперсных частиц материала и способ регенерирования фильтра-катализатора для очистки от дисперсных частиц
US9403151B2 (en) 2009-01-30 2016-08-02 Umicore Ag & Co. Kg Basic exchange for enhanced redox OS materials for emission control applications
US20120264597A1 (en) * 2009-07-20 2012-10-18 Council Of Scientific & Industrial Research CEAlO3 PEROVSKITES CONTAINING TRANSITION METAL
WO2012137930A1 (fr) * 2011-04-08 2012-10-11 トヨタ自動車株式会社 Catalyseur d'oxydation pour la purification de gaz d'échappement
WO2017130623A1 (fr) * 2016-01-28 2017-08-03 株式会社キャタラー OXYDE COMPOSITE À BASE DE Zr SUPPORTANT Pd
JP6246424B1 (ja) * 2016-01-28 2017-12-13 株式会社キャタラー Ｐｄ担持Ｚｒ系複合酸化物
CN108602049A (zh) * 2016-01-28 2018-09-28 株式会社科特拉 担载Pd的Zr系复合氧化物
US11084022B2 (en) 2016-01-28 2021-08-10 Cataler Corporation Pd-supporting Zr-based composite oxide
CN108602049B (zh) * 2016-01-28 2021-09-03 株式会社科特拉 担载Pd的Zr系复合氧化物
CN107638787A (zh) * 2017-10-17 2018-01-30 东方电气集团东方锅炉股份有限公司 一种脱除气体中氮氧化物的系统和方法
RU225095U1 (ru) * 2023-12-15 2024-04-12 Денис Сергеевич Сугатов Трехмаршрутный автомобильный катализатор, содержащий редкоземельный металл Европий, и способ его получения

Also Published As

Publication number Publication date
EP2000202A1 (fr) 2008-12-10
CA2648314C (fr) 2011-11-15
CA2648314A1 (fr) 2007-10-04
BRPI0621483A2 (pt) 2011-12-13
KR100973378B1 (ko) 2010-07-30
CN101415490A (zh) 2009-04-22
KR20090005077A (ko) 2009-01-12
EP2000202A4 (fr) 2011-05-18
US20090170689A1 (en) 2009-07-02
ZA200809153B (en) 2010-02-24
US8105561B2 (en) 2012-01-31
EP2527033A1 (fr) 2012-11-28

Similar Documents

Publication Publication Date Title
WO2007111004A1 (fr) Catalyseur de purification de gaz d'echappement, son procede de regeneration, appareil de purification de gaz d'echappement l'utilisant et procede de purification de gaz d'echappement
JP4901440B2 (ja) 排ガス浄化用触媒、その再生方法、それを用いた排ガス浄化装置及び排ガス浄化方法
JP5216189B2 (ja) 排ガス浄化用触媒
KR100881300B1 (ko) 금속 산화물 입자의 제조 공정 및 배기 가스 정화용 촉매
JP4858463B2 (ja) 排気ガス浄化用触媒およびその製造方法
EP2119491B1 (fr) Dispositif pour la purification de gaz d'echappement
RU2395341C1 (ru) Катализатор для очистки выхлопных газов, способ регенерации такого катализатора, а также устройство и способ очистки выхлопных газов при использовании данного катализатора
RU2392049C1 (ru) Частица металлоксидного носителя катализатора и катализатор очистки отходящего газа
JP2005262201A (ja) 排ガス浄化用触媒およびその製造方法
JP4465352B2 (ja) 排ガス浄化触媒
WO2017179679A1 (fr) Catalyseur d'épuration de gaz d'échappement, procédé d'épuration de gaz d'échappement et système d'épuration de gaz d'échappement
JP4979900B2 (ja) 排ガス浄化用触媒
WO2005084796A1 (fr) Catalyseur de purification de gaz d’échappement, particule d’oxyde métallique et son processus de production
JPWO2016163488A1 (ja) 内燃機関排気ガスの浄化触媒及び該触媒を用いた排気ガス浄化方法
JP5078125B2 (ja) 排ガス浄化用触媒及びその再生方法
JP5196656B2 (ja) 排ガス浄化用触媒及びその製造方法
US20200353447A1 (en) Exhaust gas-purifying three-way catalyst and method for producing same, and integral structure type exhaust gas-purifying catalyst
JP4775953B2 (ja) 排ガス浄化用触媒及びその再生方法
JP4836187B2 (ja) 排ガス浄化用触媒、並びにその製造方法及びその再生方法
JP4577408B2 (ja) 排気ガス浄化用触媒
JP4775954B2 (ja) 排ガス浄化用触媒及びその再生方法
JP2009178673A (ja) 排ガス浄化装置
WO2018088201A1 (fr) Catalyseur à trois voies de purification de gaz d'échappement, son procédé de fabrication, et convertisseur de catalyseur de purification de gaz d'échappement
JP2005342554A (ja) 触媒担体粒子及びその製造方法、並びに排ガス浄化触媒
JP2018075550A (ja) 排ガス浄化用三元触媒及びその製造方法、並びに排ガス浄化用触媒コンバータ

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 06823547

Country of ref document: EP

Kind code of ref document: A1

DPE1 Request for preliminary examination filed after expiration of 19th month from priority date (pct application filed from 20040101)
WWE Wipo information: entry into national phase

Ref document number: 2006823547

Country of ref document: EP

WWE Wipo information: entry into national phase

Ref document number: 7966/DELNP/2008

Country of ref document: IN

WWE Wipo information: entry into national phase

Ref document number: 200680054104.4

Country of ref document: CN

WWE Wipo information: entry into national phase

Ref document number: 2648314

Country of ref document: CA

NENP Non-entry into the national phase

Ref country code: DE

WWE Wipo information: entry into national phase

Ref document number: 12225692

Country of ref document: US

WWE Wipo information: entry into national phase

Ref document number: 1020087026248

Country of ref document: KR

ENP Entry into the national phase

Ref document number: 2008142533

Country of ref document: RU

Kind code of ref document: A

ENP Entry into the national phase

Ref document number: PI0621483

Country of ref document: BR

Kind code of ref document: A2

Effective date: 20080926